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We describe the Carnegie-Spitzer-IMACS (CSI) Survey, a wide-field, near-IR selected spectrophotometric redshift survey with the Inamori Magellan Areal Camera and Spectrograph (IMACS) on Magellan-Baade. By defining a flux-limited sample of galaxies in Spitzer Infrared Array Camera 3.6 μm imaging of SWIRE fields, the CSI Survey efficiently traces the stellar mass of average galaxies to z ∼ 1.5. This first paper provides an overview of the survey selection, observations, processing of the photometry and spectrophotometry. We also describe the processing of the data: new methods of fitting synthetic templates of spectral energy distributions are used to derive redshifts, stellar masses, emission line luminosities, and coarse information on recent star formation. Our unique methodology for analyzing low-dispersion spectra taken with multilayer prisms in IMACS, combined with panchromatic photometry from the ultraviolet to the IR, has yielded high-quality redshifts for 43,347 galaxies in our first 5.3 deg2 of the SWIRE XMM-LSS field. We use three different approaches to estimate our redshift errors and find robust agreement. Over the full range of 3.6 μm fluxes of our selection, we find typical redshift uncertainties of σz/(1 + z) ≲ 0.015. In comparisons with previously published spectroscopic redshifts we find scatters of σz/(1 + z) = 0.011 for galaxies at 0.7 ⩽ z ⩽ 0.9, and σz/(1 + z) = 0.014 for galaxies at 0.9 ⩽ z ⩽ 1.2. For galaxies brighter and fainter than i = 23 mag, we find σz/(1 + z) = 0.008 and σz/(1 + z) = 0.022, respectively. Notably, our low-dispersion spectroscopy and analysis yields comparable redshift uncertainties and success rates for both red and blue galaxies, largely eliminating color-based systematics that can seriously bias observed dependencies of galaxy evolution on environment. [ABSTRACT FROM AUTHOR]

Using observations from the FourStar Galaxy Evolution Survey (ZFOURGE), we obtain the deepest measurements to date of the galaxy stellar mass function (SMF) at 0.2 < z < 3. ZFOURGE provides well-constrained photometric redshifts made possible through deep medium-bandwidth imaging at 1-2 μm. We combine this with Hubble Space Telescope imaging from the Cosmic Assembly Near-IR Deep Extragalactic Legacy Survey, allowing for the efficient selection of both blue and red galaxies down to stellar masses of ∼109.5M☼ at z ∼ 2.5. The total surveyed area is 316 arcmin2 distributed over three independent fields. We supplement these data with the wider and shallower NEWFIRM Medium-Band Survey to provide stronger constraints at high masses. Several studies at z ⩽ 1.5 have revealed a steepening of the slope at the low-mass end of the SMF, leading to an upturn at masses <1010M☼ that is not well described by a standard single-Schechter function. We find evidence that this feature extends to at least z ∼ 2 and that it can be found in both the star-forming and quiescent populations individually. The characteristic mass (M*) and slope at the lowest masses (α) of a double-Schechter function fit to the SMF stay roughly constant at Log(M/M☼) ∼ 10.65 and ∼ – 1.5, respectively. The SMF of star-forming galaxies has evolved primarily in normalization, while the change in shape is relatively minor. Our data allow us, for the first time, to observe a rapid buildup at the low-mass end of the quiescent SMF. Since z = 2.5, the total stellar mass density of quiescent galaxies (down to 109M☼) has increased by a factor of ∼12, whereas the mass density of star-forming galaxies only increases by a factor of ∼2.2. [ABSTRACT FROM AUTHOR]

The BZLF1 gene controls the switch between latent and lytic infection by Epstein-Barr virus (EBV). We previously reported that both the ZV and ZIIR elements within the BZLF1 promoter, Zp, are potent transcription silencers within the context of an intact EBV genome. We report here identification of another sequence element, ZV', which synergized with ZV in repressing Zp via binding ZEB1 or ZEB2. We then determined the phenotype of a variant of EBV strain B95.8 in which the ZV, ZV', and ZIIR elements were concurrently mutated. HEK293 cell lines infected with this triple mutant (tmt) virus spontaneously synthesized 6- to 10-fold more viral BZLF1, BRLF1, BMRF1, and BLLF1 RNAs, 3- to 6-fold more viral Zta, Rta, and EAD proteins, 3- to 5-fold more viral DNA, and 7- to 9-fold more infectious virus than did 293 cell lines latently infected with either the ZV ZV' double mutant (dmt) or ZIIR mutant (mt) virus. While ZV ZV' ZIIR tmt EBV efficiently infected human primary blood B cells in vitro, it was highly defective in immortalizing them. Instead of the nearly complete silencing of BZLF1 gene expression that occurs within 4 days after primary infection with wild-type EBV, the ZV ZV' ZIIR tmt-infected cells continued to synthesize BZLF1 RNA, with 90% of them dying within 9 days postinfection. BL41 cells infected with this "superlytic" virus also exhibited increased synthesis of BZLF1 and BMRF1 RNAs. Thus, we conclude that the ZV, ZV', and ZIIR silencing elements act synergistically to repress transcription from Zp, thereby tightly controlling BZLF1 gene expression, which is crucial for establishing and maintaining EBV latency. [ABSTRACT FROM AUTHOR]

We present a multi-wavelength photometric study of ∼15,000 resolved stars in the nearby spiral galaxy M83 (NGC 5236, D = 4.61 Mpc) based on HubbleSpaceTelescope Wide Field Camera 3 observations using four filters: F336W, F438W, F555W, and F814W. We select 50 regions (an average size of 260 pc by 280 pc) in the spiral arm and inter-arm areas of M83 and determine the age distribution of the luminous stellar populations in each region. This is accomplished by correcting for extinction toward each individual star by comparing its colors with predictions from stellar isochrones. We compare the resulting luminosity-weighted mean ages of the luminous stars in the 50 regions with those determined from several independent methods, including the number ratio of red-to-blue supergiants, morphological appearance of the regions, surface brightness fluctuations, and the ages of clusters in the regions. We find reasonably good agreement between these methods. We also find that young stars are much more likely to be found in concentrated aggregates along spiral arms, while older stars are more dispersed. These results are consistent with the scenario that star formation is associated with the spiral arms, and stars form primarily in star clusters and then disperse on short timescales to form the field population. The locations of Wolf-Rayet stars are found to correlate with the positions of many of the youngest regions, providing additional support for our ability to accurately estimate ages. We address the effects of spatial resolution on the measured colors, magnitudes, and age estimates. While individual stars can occasionally show measurable differences in the colors and magnitudes, the age estimates for entire regions are only slightly affected. [ABSTRACT FROM AUTHOR]

We report the discovery of a luminous z = 5.78 star-forming galaxy in the Chandra Deep Field South. This galaxy was selected as an 'i-drop' from the GOODS public survey imaging with the Hubble Space Telescope/Advanced Camera for Surveys (object 3 in the work of Stanway, Bunker & McMahon 2003). The large colour of (I' - z')[SUBAB] = 1.6 indicated a spectral break consistent with the Lyman a forest absorption shortward of Lyman a at z &ap; 6. The galaxy is very compact (marginally resolved with ACS with a half-light radius of 0.08 arcsec, so r[SUBhl] < 0.5 h[SUP-1,SUB70] kpc). We have obtained a deep (5.5 h) spectrum of this z'[SUBAB] = 24.7 galaxy with the DEIMOS optical spectrograph on the Keck Telescope, and here we report the discovery of a single emission line centred on 8245 Å detected at 20σ with a flux of f &ap; 2 × 10[SUP-17] erg cm[SUP-2]s[SUP-1]. The line is clearly resolved with detectable structure at our resolution of better than 55 km s[SUP-1], and the only plausible interpretation consistent with the ACS photometry is that we are seeing Lyman a emission from a z = 5.78 galaxy. This is the highest redshift galaxy to be discovered and studied using HST data. The velocity width (Δν[SUBFWHM] = 260 km s[SUP-1]) and rest-frame equivalent width (W[SUPLyα,SUBrest] = 20 Å) indicate that this line is most probably powered by star formation, as an AGN would typically have larger values. The starburst interpretation is supported by our non-detection of the high-ionization N v λ 1240-Å emission line, and the absence of this source from the deep Chandra X-ray images. The star formation rate inferred from the rest-frame UV continuum is 34 h[SUP-2,SUB70] M[SUB&Odot; yr[SUP-1] (Ω[SUBM] = 0.3, Ω[SUB∇] = 0.7). This is the most luminous starburst known at z > 5. Our spectroscopic redshift for this object confirms the validity of the I' -drop technique of Stanway et al. to select star-forming... [ABSTRACT FROM AUTHOR]

A key obstacle to developing a satisfying theory of galaxy evolution is the difficulty in extending analytic descriptions of early structure formation into full non-linearity, the regime in which galaxy growth occurs. Extant techniques, though powerful, are based on approximate numerical methods whose Monte Carlo-like nature hinders intuition building. Here, we develop a new solution to this problem and its empirical validation. We first derive closed-form analytic expectations for the evolution of fixed percentiles in the real-space cosmic density distribution, averaged over representative volumes observers can track cross-sectionally. Using the Lagrangian forms of the fluid equations, we show that percentiles in δ – the density relative to the median – should grow as |$\delta (t)\propto \delta _{0}^{\alpha }\, t^{\beta }$|⁠ , where α ≡ 2 and β ≡ 2 for Newtonian gravity at epochs after the overdensities transitioned to non-linear growth. We then use 9.5 square degress of Carnegie-Spitzer-IMACS Redshift Survey data to map galaxy environmental densities over 0.2 < z < 1.5 (∼7 Gyr) and infer α = 1.98 ± 0.04 and β = 2.01 ± 0.11 – consistent with our analytic prediction. These findings – enabled by swapping the Eulerian domain of most work on density growth for a Lagrangian approach to real-space volumetric averages – provide some of the strongest evidence that a lognormal distribution of early density fluctuations indeed decoupled from cosmic expansion to grow through gravitational accretion. They also comprise the first exact, analytic description of the non-linear growth of structure extensible to (arbitrarily) low redshift. We hope these results open the door to new modelling of, and insight-building into, galaxy growth and its diversity in cosmological contexts. [ABSTRACT FROM AUTHOR]

We report the case of a 17-year-old male who was initially assessed for pain with defecation, bloody rectal discharge, and diarrhea, consistent with proctitis. Though proctitis is most commonly due to inflammatory bowel disease (IBD), infectious etiologies must also be considered, including sexually transmitted causes of infectious proctitis. In discussion of his sexual history, he identified as homosexual and acknowledged engaging in receptive anal intercourse. Rectal biopsies obtained via colonoscopy were culture-positive for herpes simplex virus (HSV), leading to a diagnosis of HSV proctitis and treatment with an appropriate antiviral medication. HSV proctitis is more common in individuals with high-risk sexual practices, including men who have sex with men. While this may be an uncommon diagnosis for pediatricians to make in practice, a high clinical index of suspicion for sexually transmitted infectious proctitis in those with risk factors must be maintained in order to facilitate appropriate testing, treatment, and counseling of affected individuals. [ABSTRACT FROM AUTHOR]

Abstract: We describe preliminary results from an ultra-sensitive, spectroscopic emission-line survey and illustrate the challenges inherent in identifying high-redshift Lyα emitters. Our multi-slit windows technique complements other types of emission-line surveys. Narrowband imaging surveys cover large areas of sky but only detect much brighter objects. Longslit spectra taken along cluster caustics yield intrinsically fainter lensed Lyα emitters but probe small volumes of space. We have observed the COSMOS deep field and a field at 15h +00. To a line flux of a few∼×10−18 ergss−1 cm−2, we found 150 emission-line sources (with no detectable continuum) among 4 masks. These candidates are being re-observed with broad spectral coverage to determine the line identity. To date, the interloper to Lyα ratio is about 8:1. The sky positions of the Lyα candidates generally do not coincide with those of foreground objects in ultra-deep r band or i′ images – consistent with the presence of a strong Lyman break. [Copyright &y& Elsevier]

Objectives: The designation of pediatric hospital medicine (PHM) as a board-certified (BC) subspecialty has led to uncertainty about the importance of PHM board certification in hiring pediatric hospitalists and ambiguity in counseling trainees interested in PHM careers about the decision to pursue fellowship. We sought to determine the importance of PHM board eligibility or certification in hiring practices., Methods: We conducted an online, cross-sectional, survey-based study of individuals who self-identified as PHM division leadership utilizing the PHM Division Director Listserv and participant recruitment at a national meeting., Results: A total of 86 responses were received. A total of 64% (30/47) of university-setting hospitals, 77% (17/28) of community hospitals, and 100% (11/11) of combined settings reported that they will hire applicants who are not board-eligible (BE) or BC (P = .83). Of the hospitals who will be hiring non-BE hospitalists, 50% of university settings, 77% of community settings, and 55% of combined settings plan to give equal consideration to both BE and non-BE applicants (P = .21). A total of 57% (21/37) of programs with a PHM fellowship felt that fellowship training was an important or very important consideration in hiring, compared with 27% (13/49) of programs without a PHM fellowship (P = .04)., Conclusions: Programs with a PHM fellowship were significantly more likely to believe that fellowship training is an important consideration in hiring hospitalists. PHM board certification and fellowship training are perceived as more important by university-based programs, although all settings will consider hiring applicants who are not BC or BE., (Copyright © 2024 by the American Academy of Pediatrics.)

Background: When unanticipated and/or poor patient outcomes occur, clinicians frequently experience guilt, anger, psychological distress, and fear, which can be intensified by traditional morbidity and mortality conferences., Methods: The Pediatric Event Review and Learning (PEaRL) curriculum was developed to discuss unanticipated and/or poor patient outcomes and foster support while highlighting foundational safety concepts. Pre- and post-implementation evaluations of quarterly cased-based sessions were completed., Results: All respondents endorsed that unanticipated and/or poor patient outcomes affected their mood, well-being, and functioning. Post-implementation of the PEaRL curriculum, significantly more respondents endorsed existence of a safe environment and structured format to discuss these outcomes, as well as feeling more supported., Discussion: The PEaRL curriculum provides a valuable opportunity for trainees and experienced clinicians alike to explore and discuss unanticipated and/or poor patient outcomes while addressing key patient safety principles., (Copyright© Board of Regents of the University of Wisconsin System and The Medical College of Wisconsin, Inc.)

Pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries (PA/VSD/MAPCAs) is a rare form of congenital heart disease. The midline unifocalization procedure has been developed for the treatment of PA/VSD/MAPCAs. These are complex and very lengthy procedures that require an entirely different method of perfusion. The purpose of this study was to review our perfusion modifications to support these unifocalization procedures. Sixty-four unifocalization procedures have been performed at our institution during the past 3 years. The median age was 4.1 months (range 1 month-3.5 years) and the median weight at surgery was 4.5 kg (range 3.5-19 kg). The median duration of cardiopulmonary bypass was 352 minutes (range 128-629 minutes), and the median duration of cross-clamp was 24 minutes (range 14-72 minutes). The conduct of surgery included cooling to a rectal perfusion temperature of 25° and a flow rate of 100 mL/kg/min. A pH-stat strategy and del Nido cardioplegia were used. Modifications to the cardiopulmonary bypass circuit include upsizing the oxygenator, reservoir, cannulae, vent catheter, and tubing. All circuits were modified to include the capability of performing an intraoperative flow study. This study is used to determine whether the VSD can be closed during surgery. A collateral flow study circuit is also set up for first-time operations to measure the residual collateral flow after all of the MAPCAs have been harvested. Patients who require midline unifocalization will invariably require very lengthy periods of support on cardiopulmonary bypass. We have adapted our perfusion circuitry to prepare for the demands on the bypass circuit to meet the requirements of this patient population. Our institution has developed a systematic approach for the conduct of perfusion to best serve our patients presenting with PA/VSD/MAPCAs.