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We study a population of significantly sub-solar enrichment galaxies at z  = 1.99, to investigate how molecular gas, dust, and star formation relate in low-metallicity galaxies at the peak epoch of star formation. We target our sample with several deep Atacama Large Millimeter/submillimeter Array and Very Large Array datasets, and find no individual detections of CO[4–3], CO[1–0], or dust, in stark contrast to the  >60 per cent detection rate expected for solar-enrichment galaxies with these MS H α star formation rates (SFRs). We find that both low- and high-density molecular gas (traced by CO[1–0] and CO[4–3], respectively) are affected by the low enrichment, showing sample average (stacked) luminosity deficits >0.5–0.7 dex below expectations. This is particularly pertinent for the use of high-J CO emission as a proxy of instantaneous SFR. Our individual galaxy data and stacked constraints point to a strong inverse dependence ∝  Z γ of gas-to-dust ratios (G/D) and CO-to-H2 conversion factors (αCO) on metallicity at z  ∼ 2, with γG/D <−2.2 and |$\gamma _{\alpha _{\rm CO}}\lt $| −0.8, respectively. We quantify the importance of comparing G/D and αCO versus metallicity trends from the literature on a common, suitably normalized metallicity scale. When accounting for systematic offsets between different metallicity scales, our z  ∼ 2 constraints on these scaling relations are consistent with the corresponding relations for local galaxies. However, among those local relations, we favour those with a steep/double power-law dependence of G/D on metallicity. Finally, we discuss the implications of these findings for (a) gas mass measurements for sub- M * galaxies, and (b) efforts to identify the characteristic galaxy mass scale contributing most to the comoving molecular gas density at z  = 2. [ABSTRACT FROM AUTHOR]

Disk galaxies at intermediate redshift (z ~ 0.7) have been found in previous work to display more optically thick behaviour than their local counterparts in the rest-frame B-band surface brightness, suggesting an evolution in dust properties over the past ~6 Gyr. We compare the measured luminosities of face-on and edge-on star-forming galaxies at different wavelengths (Ultraviolet (UV), mid-infrared (MIR), far-infrared (FIR), and radio) for two well-matched samples of disk-dominated galaxies: a local Sloan Digital Sky Survey (SDSS)-selected sample at z ~ 0.07 and a sample of disks at z ~ 0.7 drawn from Cosmic Evolution Survey (COSMOS). We have derived correction factors to account for the inclination dependence of the parameters used for sample selection. We find that typical galaxies are transparent at MIR wavelengths at both redshifts, and that the FIR and radio emission is also transparent as expected. However, reduced sensitivity at these wavelengths limits our analysis; we cannot rule out opacity in the FIR or radio. Ultra-violet attenuation has increased between z ~ 0 and z ~ 0.7, with the z ~ 0.7 sample being a factor of ~3.4 more attenuated. The larger UV attenuation at z ~ 0.7 can be explained by more clumpy dust around nascent star-forming regions. There is good agreement between the fitted evolution of the normalisation of the SFRUV versus 1 − cos(i) trend (interpreted as the clumpiness fraction) and the molecular gas fraction/dust fraction evolution of galaxies found out to z < 1. [ABSTRACT FROM AUTHOR]

HE0450-2958, an interacting quasar-starburst galaxy pair at z = 0.285, is one of the best- known examples of strong star formation activity in the presence of a quasar-driven jet. We present new multiband Karl G. Jansky Very Large Array-imaging covering 1-6 GHz and reaching an angular resolution of up to 0.6 arcsec (a sixfold improvement over existing radio data). We confirm the previous detection of a spatially extended radio component around the quasar, indicating that there is ongoing star formation activity in the quasar host galaxy. For the first time, we directly detect a jet-like bipolar outflow from the quasar aligned with its companion star-forming galaxy (SFG) and several blobs of ionized gas in its vicinity identified in previous studies. Within the companion SFG, we find evidence for a flattening of the synchrotron spectral index towards the point of intersection with the jet axis, further suggesting that the outflow may actually be impacting its interstellar medium. We discuss two possible mechanisms that could have triggered the starburst in the companion SFG: a wet-dry merger with the quasar and jet-induced star formation. While triggering through interaction-driven gas dynamics cannot be excluded with current data, our new observations make HE0450-2958 a strong candidate for jet-induced star formation, and one of the rare links between local systems (like Minkowski's Object or Centaurus A) and the high-z regime where radio-optical alignments suggest that this phenomenon could be more common. [ABSTRACT FROM AUTHOR]

Background: A pilot study of two academic training programs revealed concerning levels of resident burnout and psychological dysfunction. The purpose of the present study was to determine the quality of life of orthopaedic residents and faculty on a national scale and to identify risk factors for decompensation. Methods: Three hundred and eighty-four orthopaedic residents and 264 full-time orthopaedic faculty members completed a voluntary, anonymous survey consisting of three validated instruments (the Maslach Burnout Inventory, the General Health Questionnaire-12, and the Revised Dyadic Adjustment Scale) and question sets assessing demographic information, relationship issues, stress reactions/management, and work/life balance. Results: High levels of burnout were seen in 56% of the residents and 28% of the faculty members. Burnout risk was greatest among second-postgraduate-year residents and residents in training programs with six or more residents per postgraduate year. Sixteen percent of residents and 19% of faculty members reported symptoms of psychological distress. Sleep deprivation was common among the residents and correlated positively with every distress measure. Faculty reported greater levels of stress but greater satisfaction with work and work/life balance. A number of factors, such as making time for hobbies and limiting alcohol use, correlated with decreased dysfunction for both residents and faculty. Conclusions: Despite reporting high levels of job satisfaction, orthopaedic residents and faculty are at risk for burnout and distress. Identification of protective factors and risk factors may provide guidance to improve the quality of life of academic orthopaedic surgeons in training and beyond. [ABSTRACT FROM AUTHOR]

Background: Evaluations of physicians and residents have revealed concerning levels of psychosocial dysfunction. The purposes of this study were to determine the quality of life of orthopaedic residents and faculty and to identify the risk factors for decompensation.Methods: Twenty-one orthopaedic residents and twenty-five full-time orthopaedic faculty completed a 102-question voluntary, anonymous survey. The survey consisted of three validated instruments, i.e., the Maslach Burnout Inventory, the General Health Questionnaire-12, and the Revised Dyadic Adjustment Scale; and three novel question sets addressing background and demographic information, stress reaction and management, and the balance between work and home life. Descriptive statistics, pairwise correlations, simple t tests, and Pearson and nonparametric Spearman correlations were calculated. The simple correlation coefficient was used to assess bivariate relationships.Results: The mean overall quality-of-life score, on a scale of 0 to 4 points, was 2.5 points for residents compared with 3.6 points for faculty members. Residents reported considerable burnout, showing a high level of emotional exhaustion and depersonalization and an average level of personal achievement, whereas faculty reported minimal burnout, showing a low level of emotional exhaustion (p < 0.0003), an average level of depersonalization (p < 0.0001), and a high level of personal achievement (p < 0.0001). Only two of twenty-five faculty members (compared with seven of twenty-one residents) scored over 4 points on the General Health Questionnaire-12, indicating significant symptomatology (p < 0.01). The majority of subjects reported that a partner or spouse showed nondistressed levels of marital adjustment and satisfaction. All residents and nine of the twenty-five faculty members had mentors but judged the resource to be minimally beneficial. Resident burnout and psychiatric morbidity correlated with weekly work hours; conflict between the commitments of work and home life; discord with faculty, nursing staff, and senior residents; debt load; and work-related stress. Protective factors included being a parent, spending time with a spouse, having a physician father, and deriving satisfaction from discussing concerns with colleagues, friends, and family.Conclusions: In pursuit of our goal of determining the quality of life of orthopaedic residents and faculty, we identified a large disparity between the two groups. The resident group reported much greater levels of dysfunction particularly with regard to burnout and psychiatric morbidity. Furthermore, with regard to our second goal; our data revealed a number of risk factors for resident decompensation, most notably, increased workload, high debt levels, and discord with superiors. In addition, our research revealed that the current support interventions by the residency program, including mentoring and facilitation of spousal adjustment, are viewed as being of little help. [ABSTRACT FROM AUTHOR]

Discusses novelist D.H. Lawrence's contribution to the theoretical understanding of the dialogical imagination. Lawrence's characterization of the novel; Overview of the dialogical principle; Comparison of Lawrence to Martin Buber, Mikhail Bakhtin, Emmanuel Levinas and other novelists; Viewpoints of Jonathan Dollimore and S.P. Mohanty on commonality and difference.

Describes how peer response groups can model for students the ongoing conversation of a discipline and draw them into it, especially when assigned readings are difficult. Students' reaction to being told they will read and respond to the writing of their peers in a writing-across-the-curriculum (WAC) class; Peer response in large introductory classes; Peer response in smaller upper-level classes.

The β2-integrin Family of adhesion molecules and their ligands. The ICAM molecules, probably have an important role to play in the intestinal immune response. To date, any data published regarding the intestinal expression or β2-integrins and ICAMs have mostly described only mucosal expression. The presence in the intestine of αd, a newly described β2-integrin molecule has not yet been determined. To understand further the expression of these molecules in all layers of the intestine, a comprehensive study was undertaken in both normal colon and normal small intestine specimens from 15 patients (colon n = 15. and ileum n = 6) who underwent surgical resections. Immunohistochemistry was performed for CD18, CD11a. CD11 b. CD11c. αd. ICAM-1, ICAM-2. and ICAM-3. The colon and small intestine cases were grouped separately and each of the mucosal, submucosal, muscle and adventitial layers were scored for expression. The β2-integrin molecules were expressed by mononuclear cells in all layers of the bowel, predominantly in the mucosa and adventitia. CD11a showed the greatest mucosal expression and CD11b showed the greatest adventitial expression, αd exhibited expression in all bowel layers, as well, with most intense expression in the mucosa and adventitia. CD11c exhibited the least expression of all α subunit molecules. The expression of these α-chains at times appeared to be greater than that seen for CD18 (β2), raising the possibility of non-β2-containing complexes (i.e. α-chains associating with an alternate β-chain). ICAM-l was expressed on endotheiium, particularly in the mucosa and rarely on mucosal mononuclear cells. ICAM-2 was predominantly on subtiuicosal endothelium and rarely expressed in colon mucosa and never expressed in ileal mucosa. ICAM-3 was expressed by mononuclear cells throughout the bowel wall, but also on adventitial endothelium in selected eases. In summary, we are reporting a comprehensive immunohistochemical study of the differential expression of β2-integrins, including the newly described αd molecule and the ICAM molecules in all layers of normal human colon and ileum. We raise the possibility that a second β2-integrin 3 subunit may exist, and we report that lCAM-3 is expressed on endothelium particularly in the adventitial layer. [ABSTRACT FROM AUTHOR]

Investigating the thermal and non-thermal processes in galaxies is vital to understand their evolution over cosmic time. This can best be studied by combining the radio and optical/near-infrared observations of galaxies. The JWST can resolve the evolution of the thermal processes by mapping ionized gas and dust in distant galaxies. This information combined with the upcoming surveys with the Square Kilometer Array (SKA) will make a major breakthrough in mapping the non-thermal processes and understanding their role in the evolution of galaxies. Our simulations show that SKA surveys will be able to trace the evolution history of spiral galaxies such as M 51 and NGC 6946 back to a redshift of 3 already in its first phase of construction. This study indicates the important role of the non-thermal pressure inserted by cosmic rays and magnetic fields in deriving winds and outflows at cosmic noon as deduced by a flat synchrotron spectrum in star forming galaxies. [ABSTRACT FROM AUTHOR]

The unique characteristics of the brightest group galaxies (BGGs) serve as a link in the evolutionary continuum between galaxies such as the Milky Way and the more massive brightest cluster galaxies found in dense clusters. This research investigates the evolution of the stellar properties of BGGs over cosmic time (z = 0.08 − 1.30), extending the work from our prior studies. We analyzed the data of 246 BGGs selected from our X-ray galaxy group catalog within the COSMOS field, examining stellar age, mass, star-formation rate (SFR), specific SFR, and halo mass. We compared observations with the Millennium and Magneticum simulations. Additionally, we investigated whether stellar properties vary with the projected offset from the X-ray peak or the hosting halo center. We evaluated the accuracy of SED-derived stellar ages using a mock galaxy catalog, finding a mean absolute error of around 1 Gyr. Interestingly, the observed BGG age distributions exhibit a bias toward younger intermediate ages compared to both semi-analytical models and the Magneticum simulation. Our analysis of stellar age versus mass unveils intriguing trends with a positive slope, hinting at complex evolutionary pathways across redshifts. We observed a negative correlation between stellar age and SFR across all redshift ranges. We employed a cosmic time dependent main sequence framework to identify star forming BGGs and find that approximately 20% of BGGs in the local universe continue to exhibit characteristics typical of star forming galaxies, with this proportion increasing to 50% at z = 1.0. Our findings support an inside-out formation scenario for BGGs, where older stellar populations reside near the X-ray peak and younger populations at larger offsets indicate ongoing star-formation. The observed distribution of stellar ages, particularly for lower-mass BGGs in the range of 1010−11 M⊙, deviates from the constant ages predicted by the models across all stellar mass ranges and redshifts. This discrepancy aligns with the current models' known limitations in accurately capturing galaxies' complex star-formation histories. [ABSTRACT FROM AUTHOR]

Use of a single-leg spica cast for femoral fractures in ambulatory children 1 to 5 years of age facilitates care and mobilization of the patient. Itmay allow a shorter duration of cast treatment than is possible with a traditional one and one-half-leg spica cast, particularly in patients 1 to 3 years of age. The single-leg spica is indicated for children who are small enough to be lifted safely in the cast and who have an isolated, closed, low-energy femoral shaft fracture. The procedure consists of the following steps: * Step 1: Obtain adequate sedation. General anesthesia should be used in the operating room, whereas conscious sedation may be used in the emergency or procedure room setting. The location of the procedure should be determined by available resources. * Step 2: Determine the position of optimal alignment by visual examination of the thigh and leg. If intraoperative imaging is available, assess fracture stability by performing the telescope test described by Thompson et al.1--i.e., by gently applying axial load to the thigh to assess for shortening under fluoroscopic monitoring. Shortening of .3 cm reflects substantial periosteal stripping and is associated with an increased risk of loss of reduction in the cast. Alternative stabilization techniques should be considered for grossly unstable fractures with a positive telescope test. Use of intramedullary nails, external fixation, or traction with delayed cast application may decrease the risk of excessive shortening or unacceptable angulation of the fracture in the cast. * Step 3: Apply a stockinette or waterproof pantaloons cast liner to the torso and involved lower extremity. * Step 4: Position the patient on a spica-cast application table, which provides a support under the thorax and head with a strut that supports the spine and pelvis to the sacrum, allowing application of the cast material to the pelvic area and involved extremity. Position the patient on the table with the involved extremity flexed 30° to 60° at the hip and 30° to 60° at the knee and the contralateral leg supported. Greater flexion makes it easier to fit the child into a car seat or high chair and to carry him/her on the caretaker's hip, whereas flexing the hip and knee less allows the patient to bear weight more easily. However, Illgen et al.2 found knee flexion of,50° to be associated with an increased risk of reduction loss. More proximal fractures are better treated with greater hip flexion because of their tendency to drift into apex anterior angulation. * Step 5: Overwrap the cast liner from nipple line to ankle with cotton or synthetic undercast padding to prevent pressure sores. Some families prefer waterproof cast padding as it allows the child to be immersed for bathing, but it provides less padding at pressure points and increases the cost of the cast. * Step 6: Apply fiberglass or plaster cast material starting 1 in (2.5 cm) below the edge of the cast padding and ending 1 in above the malleoli to allow the edges of the cast to be adequately padded when the liner is folded back. * Step 7: Apply an iliac crest mold to stabilize the hip, and apply an anterior and valgus mold to the involved thigh to recreate the anterior bow and address the tendency of femoral shaft fractures to drift into varus. * Step 8: Trim and finish the cast. Inspect the groin region for rough edges and trim them as needed using the cast saw or bandage scissors. Cast edges should be "petalled with" (covered with short strips of) moleskin as needed. * Step 9: After the cast is hard, remove the patient from the spica table and wake him/her up. Place a smaller diaper over the groin inside the cast to prevent cast soiling and a second, larger diaper over the outside of the cast to hold the smaller diaper in place. Following cast application, distal neurovascular status is assessed. The caretakers are trained in cast care and safe patient transport. The fit of the car seat is checked prior to discharge from the emergency room or hospital. Follow-up radiographs with the patient in the cast should be obtained 10 days after cast application. Angulation of ≤15° and shortening of <2 cm can generally be accepted in patients with a midshaft fracture. Angulation of >15° can often be managed with wedging of the cast in the clinic. Excessive shortening may require reapplication of the cast or a change to another stabilization method. Single-leg spica treatment of femoral fractures in children ≤5 years of age has provided reliable outcomes with few complications. Usually, the cast can be removed 4 to 6 weeks following application. [ABSTRACT FROM AUTHOR]

We investigate the fraction of close pairs and morphologically identified mergers on and above the star-forming main sequence (MS) at 0.2 ≤  z  ≤2.0. The novelty of our work lies in the use of a non-parametric morphological classification performed on resolved stellar mass maps, reducing the contamination by non-interacting, high-redshift clumpy galaxies. We find that the merger fraction rapidly rises to ≥70 per cent above the MS, implying that – already at z ≳ 1 – starburst (SB) events (ΔMS ≥ 0.6) are almost always associated with a major merger (1:1 to 1:6 mass ratio). The majority of interacting galaxies in the SB region are morphologically disturbed, late-stage mergers. Pair fractions show little dependence on MS offset and pairs are more prevalent than late-stage mergers only in the lower half of the MS. In our sample, major mergers on the MS occur with a roughly equal frequency of ∼5–10 per cent at all masses ≳ 1010  M ⊙. The MS major merger fraction roughly doubles between z = 0.2 and 2, with morphological mergers driving the overall increase at z ≳ 1. The differential redshift evolution of interacting pairs and morphologically classified mergers on the MS can be reconciled by evolving observability time-scales for both pairs and morphological disturbances. The observed variation of the late-stage merger fraction with ΔMS follows the perturbative 2-Star Formation Mode model, where any MS galaxy can experience a continuum of different star formation rate enhancements. This points to an SB–merger connection not only for extreme events, but also more moderate bursts which merely scatter galaxies upward within the MS, rather than fully elevating them above it. [ABSTRACT FROM AUTHOR]

Star-forming galaxies (SFGs) display a continuous specific star formation rate (sSFR) distribution, which can be approximated by two log-normal functions: one encompassing the galaxy main sequence (MS), and the other a rarer, starbursting population. Starburst (SB) sSFRs can be regarded as the outcome of a physical process (plausibly merging) taking the mathematical form of a log-normal boosting kernel that enhances star formation activity. We explore the utility of splitting the star-forming population into MS and SB galaxies—an approach we term the “2-Star Formation Mode” framework—for understanding their molecular gas properties. Star formation efficiency (SFE) and gas fraction variations among SFGs take a simple redshift-independent form, once these quantities are normalized to the corresponding values for average MS galaxies. SFE enhancements during SB episodes scale supra-linearly with the SFR increase, as expected for mergers. Consequently, galaxies separate more clearly into loci for SBs and normal galaxies in the Schmidt-Kennicutt plane than in (s)SFR versus M⋆ space. SBs with large deviations (>10 fold) from the MS, e.g., local ULIRGs, are not average SBs, but are much rarer events whose progenitors had larger gas fractions than typical MS galaxies. Statistically, gas fractions in SBs are reduced two- to threefold compared to their direct MS progenitors, as expected for short-lived SFR boosts where internal gas reservoirs are depleted more quickly than gas is re-accreted from the cosmic web. We predict variations of the conversion factor αCO in the SFR-M⋆ plane and we show that the higher sSFR of distant galaxies is directly related to their larger gas fractions. [ABSTRACT FROM AUTHOR]

We present a new instrument for the measurement of water vapor in the upper troposphere and lower stratosphere (UT/LS), the Harvard Herriott Hygrometer (HHH). HHH employs a tunable diode near-IR laser to measure water vapor via direct absorption in a Herriott cell. The direct absorption technique provides a direct link between the depth of the observed absorption line and the measured water vapor concentration, which is calculated based on spectroscopic parameters in the HITRAN database. While several other tunable diode laser (TDL) instruments have been used to measure water vapor in the UT/LS, HHH is set apart by its use of an optical cell an order of magnitude smaller than those of other direct absorption TDLs in operation, allowing for a more compact, lightweight instrument. HHH is also unique in its integration into a common duct with the Harvard Lyman-α hygrometer, an independent photo-fragment fluorescence instrument which has been thoroughly validated over 19 years of flight measurements. The instrument was flown for the first time in the Mid-latitude Airborne Cirrus Properties Experiment (MACPEX) on NASA's WB-57 aircraft in spring, 2011, during which it demonstrated in-flight precision of 0.1 ppmv (1 s) with 1-sigma uncertainty of 5% ± 0.7 ppmv. Since the campaign, changes to the instrument have lead to improved accuracy of 5% ± 0.2 ppmv as demonstrated in the laboratory. During MACPEX, HHH successfully measured water vapor at concentrations from 3.5 to 600 ppmv in the upper troposphere and lower stratosphere. HHH and Lyman-α, measuring independently but under the same sampling conditions, agreed on average to within 1% at water vapor mixing ratios above 20 ppmv and to within 0.3 ppmv at lower mixing ratios. HHH also agreed with a number of other in situ water vapor instruments on the WB-57 to within their stated uncertainties, and to within 0.7 ppmv at low water. This agreement constitutes a significant improvement over past in situ comparisons, in which differences of 1.5-2 ppmv were routinely observed, and demonstrates that the accuracy of HHH is consistent with other instruments which use a range of detection methods and sampling techniques. [ABSTRACT FROM AUTHOR]

Background: Orthopaedic residents and attending physicians who report having a supportive spouse show lower levels of burnout and psychological distress than those without supportive spouses. However, little is known about the experiences of the spouses. This nationwide study examines burnout, psychological distress, and marital satisfaction of the spouses and significant others (collectively referred to hereafter as spouses) of orthopaedists in trainingand in orthopaedic practice in an academic setting. Methods: Employing previously reported methodology, 259 spouses of orthopaedic residents and 169 spouses of full-time orthopaedic faculty completed a voluntary, anonymous survey. The survey included three validated instruments (the Maslach Burnout Inventory, the General Psychological Health Questionnaire-12, and the Revised Dyadic Adjustment Scale) and three novel question sets addressing demographic information, relationship issues, stress, and work/life balance. Results: Psychological distress was noted in 18% of resident spouses compared with only 10% of faculty spouses (p = 0.014). Resident spouses reported greater loneliness (p < 0.0009) and stress (p = 0.03) than faculty spouses. Among working spouses, 30% of resident spouses and 13% of faculty spouses showed high levels of emotional exhaustion (p < 0.003). Twenty-eight percent of employed resident spouses and 5% of employed faculty spouses showed problematic levels of depersonalization (p < 0.0001). Twenty-six percent of employed resident spouses and 12% of employed faculty spouses showed a diminished sense of personal accomplishment (p = 0.012). Marital satisfaction was high for both resident and faculty spouses. Decreased satisfaction correlated with excessive mate irritability and fatigue that precluded their mate's involvement in family activities. A gratifying sex life, full-time work outside the home, and spending more than ninety minutes a day with their mate correlated significantly with marital satisfaction. Conclusions: Many orthopaedic resident spouses showed elevated levels of burnout, and a substantial number showed psychological distress. Spouses of orthopaedic faculty surgeons showed low rates of burnout and psychological dis-tress. While both resident and faculty spouses reported high levels of marital satisfaction, the engagement of their surgeon mates had a considerable impact on the well-being of the relationship. [ABSTRACT FROM AUTHOR]

An abstract of the article "Managing Stress in the Orthopaedic Family: Avoiding Burnout, Achieving Resilience," by M. Catherine Sargent and colleagues is presented.

Our current understanding of the cosmic star formation history at z > 3 is primarily based on UV-selected galaxies (Lyman-break galaxies, i.e., LBGs). Recent studies of H-dropouts (HST-dark galaxies) have revealed that we may be missing a large proportion of star formation that is taking place in massive galaxies at z > 3. In this work, we extend the H-dropout criterion to lower masses to select optically dark or faint galaxies (OFGs) at high redshifts in order to complete the census between LBGs and H-dropouts. Our criterion (H > 26:5 mag & [4.5] < 25 mag) combined with a de-blending technique is designed to select not only extremely dust-obscured massive galaxies but also normal star-forming galaxies (typically E(B V) > 0:4) with lower stellar masses at high redshifts. In addition, with this criterion, our sample is not contaminated by massive passive or old galaxies. In total, we identified 27 OFGs at zphot > 3 (with a median of zmed = 4:1) in the GOODS-ALMA field, covering a wide distribution of stellar masses with log(MM) = 9:411:1 (with a median of log(Med/M) = 10.3). We find that up to 75% of the OFGs with log(M/M) = 9:510:5 were neglected by previous LBGs and H-dropout selection techniques. After performing an optical-to-millimeter stacking analysis of the OFGs, we find that rather than being limited to a rare population of extreme starbursts, these OFGs represent a normal population of dusty star-forming galaxies at z > 3. The OFGs exhibit shorter gas depletion timescales, slightly lower gas fractions, and lower dust temperatures than the scaling relation of typical star-forming galaxies. Additionally, the total star formation rate (SFRtot = SFRIR + SFRUV) of the stacked OFGs is much higher than the SFRcorr UV (SFRUV corrected for dust extinction), with an average SFRtot/SFRcorr UV = 8 ± 1, which lies above (~0.3 dex) the 16-84th percentile range of typical star-forming galaxies at 3 z 6. All of the above suggests the presence of hidden dust regions in the OFGs that absorb all UV photons, which cannot be reproduced with dust extinction corrections. The effective radius of the average dust size measured by a circular Gaussian model fit in the uv plane is Re(1:13 mm) = 1:01 ± 0:05 kpc. After excluding the five LBGs in the OFG sample, we investigated their contributions to the cosmic star formation rate density (SFRD). We found that the SFRD at z > 3 contributed by massive OFGs (log(MM) > 10:3) is at least two orders of magnitude higher than the one contributed by equivalently massive LBGs. Finally, we calculated the combined contribution of OFGs and LBGs to the cosmic SFRD at z = 45 to be 4 102 M yr1 Mpc3, which is about 0.15 dex (43%) higher than the SFRD derived from UV-selected samples alone at the same redshift. This value could be even larger, as our calculations were performed in a very conservative way. [ABSTRACT FROM AUTHOR]

The evolution of the dust grain size distribution has been studied in recent years with great detail in cosmological hydrodynamical simulations taking into account all the channels under which dust evolves in the interstellar medium. We present a systematic analysis of the observed spectral energy distribution of a large sample of galaxies in the local Universe in order to derive not only the total dust masses but also the relative mass fraction between small and large dust grains (DS / DL). Simulations reproduce fairly well the observations except for the high-stellar mass regime where dust masses tend to be overestimated. We find that ∼45 per cent of galaxies exhibit DS / DL consistent with the expectations of simulations, while there is a subsample of massive galaxies presenting high DS / DL (log (DS / DL) ∼ −0.5), and deviating from the prediction in simulations. For these galaxies which also have high-molecular gas mass fractions and metallicities, coagulation is not an important mechanism affecting the dust evolution. Including diffusion, transporting large grains from dense regions to a more diffuse medium where they can be easily shattered, would explain the observed high DS / DL values in these galaxies. With this study, we reinforce the use of the small-to-large grain mass ratio to study the relative importance of the different mechanisms in the dust life cycle. Multiphase hydrodynamical simulations with detailed feedback prescriptions and more realistic subgrid models for the dense phase could help to reproduce the evolution of the dust grain size distribution traced by observations. [ABSTRACT FROM AUTHOR]

Using a phenomenological approach, we self-consistently model the redshift evolution of the ultraviolet (UV) and infrared (IR) luminosity functions across cosmic time, as well as a range of observed IR properties of UV-selected galaxy population. This model is an extension of the 2SFM (2 star formation modes) formalism, which is based on the observed ‘main sequence’ of star-forming galaxies, i.e. a strong correlation between their stellar mass and their star formation rate, and a secondary population of starbursts with an excess of star formation. The balance between the UV light from young, massive stars and the dust-reprocessed IR emission is modelled following the empirical relation between the attenuation (IRX for IR excess hereafter) and the stellar mass, assuming a scatter of 0.4 dex around this relation. We obtain good overall agreement with the measurements of the IR luminosity function up to z ∼ 3 and the UV luminosity functions up to z ∼ 6, and show that a scatter on the IRX–M relation is mandatory to reproduce these observables. We also naturally reproduce the observed, flat relation between the mean IRX and the UV luminosity at LUV > 109.5 L⊙. Finally, we perform predictions of the UV properties and detectability of IR-selected samples and the vice versa, and discuss the results in the context of the UV-rest-frame and sub-millimetre surveys of the next decade. [ABSTRACT FROM AUTHOR]

We present direct constraints on the CO luminosity function at high redshift and the resulting cosmic evolution of the molecular gas density, (z), based on a blind molecular line scan in the Hubble Deep Field North (HDF-N) using the IRAM Plateau de Bure Interferometer. Our line scan of the entire 3 mm window (79-115 GHz) covers a cosmic volume of ∼7000 Mpc3, and redshift ranges z < 0.45, 1.01 < z < 1.89 and z > 2. We use the rich multiwavelength and spectroscopic database of the HDF-N to derive some of the best constraints on CO luminosities in high redshift galaxies to date. We combine the blind CO detections in our molecular line scan (presented in a companion paper) with stacked CO limits from galaxies with available spectroscopic redshifts (slit or mask spectroscopy from Keck and grism spectroscopy from the Hubble Space Telescope) to give first blind constraints on high-z CO luminosity functions and the cosmic evolution of the H2 mass density (z) out to redshifts z ∼ 3. A comparison to empirical predictions of (z) shows that the securely detected sources in our molecular line scan already provide significant contributions to the predicted (z) in the redshift bins 〈 z〉 ∼ 1.5 and 〈 z〉 ∼ 2.7. Accounting for galaxies with CO luminosities that are not probed by our observations results in cosmic molecular gas densities (z) that are higher than current predictions. We note, however, that the current uncertainties (in particular the luminosity limits, number of detections, as well as cosmic volume probed) are significant, a situation that is about to change with the emerging ALMA observatory. [ABSTRACT FROM AUTHOR]

Compact star formation appears to be generally common in dusty star-forming galaxies (SFGs). However, its role in the framework set by the scaling relations in galaxy evolution remains to be understood. In this work we follow up on the galaxy sample from the GOODS-ALMA 2.0 survey, an ALMA blind survey at 1.1 mm covering a continuous area of 72.42 arcmin2 using two array configurations. We derived physical properties, such as star formation rates, gas fractions, depletion timescales, and dust temperatures for the galaxy sample built from the survey. There exists a subset of galaxies that exhibit starburst-like short depletion timescales, but they are located within the scatter of the so-called main sequence of SFGs. These are dubbed starbursts in the main sequence and display the most compact star formation and they are characterized by the shortest depletion timescales, lowest gas fractions, and highest dust temperatures of the galaxy sample, compared to typical SFGs at the same stellar mass and redshift. They are also very massive, accounting for ∼60% of the most massive galaxies in the sample (log(M*/M⊙) > 11.0). We find trends between the areas of the ongoing star formation regions and the derived physical properties for the sample, unveiling the role of compact star formation as a physical driver of these properties. Starbursts in the main sequence appear to be the extreme cases of these trends. We discuss possible scenarios of galaxy evolution to explain the results drawn from our galaxy sample. Our findings suggest that the star formation rate is sustained in SFGs by gas and star formation compression, keeping them within the main sequence even when their gas fractions are low and they are presumably on the way to quiescence. [ABSTRACT FROM AUTHOR]

Background: Previous studies have reported disparities in orthopaedic care resulting from demographic factors, including insurance status. However, the effect of insurance on pediatric tibial spine fractures (TSFs), an uncommon but significant injury, is unknown. Purpose: To assess the effect of insurance status on the evaluation and treatment of TSFs in children and adolescents. Study Design: Cross-sectional study; Level of evidence, 3. Methods: We performed a retrospective cohort study of TSFs treated at 10 institutions between 2000 and 2019. Demographic data were collected, as was information regarding pre-, intra-, and postoperative treatment, with attention to delays in management and differences in care. Surgical and nonsurgical fractures were included, but a separate analysis of surgical patients was performed. Univariate analysis was followed by purposeful entry multivariate regression to adjust for confounding factors. Results: Data were collected on 434 patients (mean ± SD age, 11.7 ± 3.0 years) of which 61.1% had private (commercial) insurance. Magnetic resonance imaging (MRI) was obtained at similar rates for children with public and private insurance (41.4% vs 41.9%, respectively; P ≥.999). However, multivariate analysis revealed that those with MRI performed ≥21 days after injury were 5.3 times more likely to have public insurance (95% CI, 1.3-21.7; P =.02). Of the 434 patients included, 365 required surgery. Similar to the overall cohort, those in the surgical subgroup with MRI ≥21 days from injury were 4.8 times more likely to have public insurance (95% CI, 1.2-19.6; P =.03). Children who underwent surgery ≥21 days after injury were 2.5 times more likely to have public insurance (95% CI, 1.1-6.1; P =.04). However, there were no differences in the nature of the surgery or findings at surgery. Those who were publicly insured were 4.1 times more likely to be immobilized in a cast rather than a brace postoperatively (95% CI, 2.3-7.4; P <.001). Conclusion: Children with public insurance and a TSF were more likely to experience delays with MRI and surgical treatment than those with private insurance. However, there were no differences in the nature of the surgery or findings at surgery. Additionally, patients with public insurance were more likely to undergo postoperative casting rather than bracing. [ABSTRACT FROM AUTHOR]

The high-frequency radio sky has historically remained largely unexplored due to the typical faintness of sources in this regime, and the modest survey speed compared to observations at lower frequencies. However, high-frequency radio surveys offer an invaluable tracer of high-redshift star formation, as they directly target the faint radio free–free emission. We present deep continuum observations at 34 GHz in the COSMOS and GOODS-North fields from the Karl G. Jansky Very Large Array (VLA), as part of the COLDz survey. The deep COSMOS mosaic spans down to σ = 1.3 μJy beam−1, while the wider GOODS-N observations cover to σ = 5.3 μJy beam−1. We detect a total of 18 galaxies at 34 GHz, of which nine show radio emission consistent with being powered by star formation; although for two sources, this is likely due to thermal emission from dust. Utilizing deep ancillary radio data at 1.4, 3, 5, and 10 GHz, we decompose the spectra of the remaining seven star-forming galaxies into their synchrotron and thermal free–free components, and find typical thermal fractions and synchrotron spectral indices comparable to those observed in local star-forming galaxies. We further determine free–free star formation rates (SFRs), and show that these are in agreement with SFRs from spectral energy distribution-fitting and the far-infrared/radio correlation. Our observations place strong constraints on the high-frequency radio emission in typical galaxies at high redshift, and provide some of the first insights into what is set to become a key area of study with future radio facilities, such as the Square Kilometer Array Phase 1 and next-generation VLA. [ABSTRACT FROM AUTHOR]

We present Herschel –PACS spectroscopy of four main-sequence star-forming galaxies at z ∼ 1.5. We detect [OI]63  μ m line emission in BzK-21000 at z  = 1.5213, and measure a line luminosity, |$L_{\rm [O\, {\small I}]63\, \mu m} = (3.9\pm 0.7)\times 10^9$|  L⊙. Our PDR modelling of the interstellar medium in BzK-21000 suggests a UV radiation field strength, G ∼ 320 G 0, and gas density, n ∼ 1800 cm−3, consistent with previous LVG modelling of the molecular CO line excitation. The other three targets in our sample are individually undetected in these data, and we perform a spectral stacking analysis which yields a detection of their average emission and an [O  i ]63  μ m line luminosity, |$L_{\rm [O\, {\small I}]63\, \mu m} = (1.1\pm 0.2)\times 10^9$|  L⊙. We find that the implied luminosity ratio, |$L_{\rm [O\, {\small I}]63\, \mu m}/L_{\rm IR}$|⁠ , of the undetected BzK-selected star-forming galaxies broadly agrees with that of low-redshift star-forming galaxies, while BzK-21000 has a similar ratio to that of a dusty star-forming galaxy at z ∼ 6. The high [O  i ]63  μ m line luminosities observed in BzK-21000 and the z ∼ 1−3 dusty and sub-mm luminous star-forming galaxies may be associated with extended reservoirs of low density, cool neutral gas. [ABSTRACT FROM AUTHOR]

We investigate the properties of a sample of 35 galaxies, detected with the Atacama Large Millimeter/Submillimeter Array (ALMA) at 1.1 mm in the GOODS-ALMA field (area of 69 arcmin2, resolution = 0.60″, rms ≃ 0.18 mJy beam−1). Using the ultraviolet-to-radio deep multiwavelength coverage of the GOODS–South field, we fit the spectral energy distributions of these galaxies to derive their key physical properties. The galaxies detected by ALMA are among the most massive at z = 2−4 (M⋆, med = 8.5 × 1010M⊙) and they are either starburst or located in the upper part of the galaxy star-forming main sequence. A significant portion of our galaxy population (∼40%), located at z ∼ 2.5 − 3, exhibits abnormally low gas fractions. The sizes of these galaxies, measured with ALMA, are compatible with the trend between the rest-frame 5000 Å size and stellar mass observed for z ∼ 2 elliptical galaxies, suggesting that they are building compact bulges. We show that there is a strong link between star formation surface density (at 1.1 mm) and gas depletion time: The more compact a galaxy's star-forming region is, the shorter its lifetime will be (without gas replenishment). The identified compact sources associated with relatively short depletion timescales (∼100 Myr) are the ideal candidates to be the progenitors of compact elliptical galaxies at z ∼ 2. [ABSTRACT FROM AUTHOR]

We present an analysis of the dust attenuation of star-forming galaxies at z  = 2.5–4.0 through the relationship between the UV spectral slope (β), stellar mass (M *), and the infrared excess (IRX = L IR/ L UV) based on far-infrared continuum observations from the Atacama Large Millimeter/sub-millimeter Array (ALMA). Our study exploits the full ALMA archive over the COSMOS field processed by the A3COSMOS team, which includes an unprecedented sample of ∼1500 galaxies at z ∼ 3 as primary or secondary targets in ALMA band 6 or 7 observations with a median continuum sensitivity of 126 |$\rm {\mu Jy\, beam}^{-1}$| (1σ). The detection rate is highly mass dependent, decreasing drastically below log (M */M⊙) = 10.5. The detected galaxies show that the IRX–β relationship of massive (log  M */M⊙ > 10) main-sequence galaxies at z  = 2.5–4.0 is consistent with that of local galaxies, while starbursts are generally offset by |$\sim 0.5\, {\rm dex}$| to larger IRX values. At the low-mass end, we derive upper limits on the infrared luminosities through stacking of the ALMA data. The combined IRX– M * relation at |$\rm {log\, ({\it M}_{\ast }/\mathrm{M}_{\odot })\gt 9}$| exhibits a significantly steeper slope than reported in previous studies at similar redshifts, implying little dust obscuration at log  M */M⊙ < 10. However, our results are consistent with earlier measurements at z ∼ 5.5, indicating a potential redshift evolution between z ∼ 2 and z ∼ 6. Deeper observations targeting low-mass galaxies will be required to confirm this finding. [ABSTRACT FROM AUTHOR]

We present Atacama Large Millimetre Array and Atacama Compact Array observations of the Sunyaev-Zel'dovich effect in the z = 2 galaxy cluster Cl J1449+0856, an X-ray-detected progenitor of typical massive clusters in the present day Universe. While in a cleaned but otherwise untouched 92 GHz map of this cluster little to no negative signal is visible, careful subtraction of known sub-millimetre emitters in the uv plane reveals a decrement at 5σ significance. The total signal is −190 ± 36 μJy, with a peak offset by 5″–9″ (∼50 kpc) from both the X-ray centroid and the still-forming brightest cluster galaxy. A comparison of the recovered uv-amplitude profile of the decrement with different pressure models allows us to derive total mass constraints consistent with the ∼6 × 1013M⊙ estimated from X-ray data. Moreover, we find no strong evidence for a deviation of the pressure profile with respect to local galaxy clusters, although a slight tension at small-to-intermediate spatial scales suggests a flattened central profile, opposite to that seen in a cool core and possibly an AGN-related effect. This analysis of the lowest mass single SZ detection so far illustrates the importance of interferometers when observing the SZ effect in high-redshift clusters, the cores of which cannot be considered quiescent, such that careful subtraction of galaxy emission is necessary. [ABSTRACT FROM AUTHOR]

Context. Given the unprecedented depth achieved in current large radio surveys, we are starting to probe populations of radio sources that have not been studied in the past. However, identifying and categorising these objects, differing in size, shape and physical properties, is becoming a more difficult task. Aims. In this data paper we present and characterise the multi-component radio sources identified in the VLA-COSMOS Large Project at 3 GHz (0.75 arcsec resolution, 2.3 μJy beam−1 rms), i.e. the radio sources which are composed of two or more radio blobs. Methods. The classification of objects into multi-components was done by visual inspection of 351 of the brightest and most extended blobs from a sample of 10,899 blobs identified by the automatic code BLOBCAT. For that purpose we used multi-wavelength information of the field, such as the 1.4 GHz VLA-COSMOS data and the Ultra Deep Survey with the VISTA telescope (UltraVISTA) stacked mosaic available for COSMOS. Results. We have identified 67 multi-component radio sources at 3 GHz: 58 sources with active galactic nucleus (AGN) powered radio emission and nine star-forming galaxies. We report eight new detections that were not observed by the VLA-COSMOS Large Project at 1.4 GHz, due to the slightly larger area coverage at 3 GHz. The increased spatial resolution of 0.75 arcsec has allowed us to resolve (and isolate) multiple emission peaks of 28 extended radio sources not identified in the 1.4 GHz VLA-COSMOS map. We report the multi-frequency flux densities (324 MHz, 325 MHz, 1.4 GHz & 3 GHz), star formation rates, and stellar masses of these objects. We find that multi-component objects at 3 GHz VLA-COSMOS inhabit mainly massive galaxies (> 1010.5 M⊙). The majority of the multi-component AGN lie below the main sequence of star-forming galaxies (SFGs), in the green valley and the quiescent region. Furthermore, we provide detailed descriptions of the objects and find that amongst the AGN there are two head-tail, ten core-lobe, nine wide-angle-tail (WAT), eight double-double or Z-/X-shaped, three bent-tail radio sources, and 26 symmetric sources, while amongst the SFGs we find the only star-forming ring seen in radio emission in COSMOS. Additionally, we report a large number (32 out of 58) of disturbed/bent multi-component AGN, 18 of which do not lie within X-ray groups in COSMOS (redshift range 0.08 ≤ z <  1.53). Conclusion. The high angular resolution and sensitivity of the 3 GHz VLA-COSMOS data set give us the opportunity to identify peculiar radio structures and sub-structures of multi-component objects, and relate them to physical phenomena such as AGN or star-forming galaxies. This study illustrates the complexity of the μJy radio-source population; at the sensitivity and resolution of 3 GHz VLA-COSMOS, the radio structures of AGN and SFG both emitting radio continuum emission, become comparable in the absence of clear, symmetrical jets. Thus, disentangling the AGN and SFG contributions using solely radio observations can be misleading in a number of cases. This has implications for future surveys, such as those done by square kilometre array (SKA) and precursors, which will identify hundreds of thousands of multi-component objects. [ABSTRACT FROM AUTHOR]

We present deep continuum observations at a wavelength of 2 mm centered on the COSMOS field using the Goddard IRAM Superconducting Millimeter Observer (GISMO) at the IRAM 30 m telescope. These data constitute the widest deep 2 mm survey to date, reaching a uniform σ ∼ 0.23 mJy beam−1 sensitivity over ∼250 arcmin2 at ∼24″ resolution. We detect four sources at high significance (S/N ≥ 4.4) with an expected number of false detections of 0.09 sources and five sources at 4.4 > S/N ≥ 3.7 with an expected number of false detections of 1.65 sources. Combined with deep GISMO observations in GOODS-N, we constrain the 2 mm number counts over one decade in flux density. These measurements agree with most galaxy evolution models tested here, except those with a large population of dusty star-forming galaxies at z > 7. Five GISMO sources have counterparts in (sub)millimeter catalogs available in COSMOS. Their redshifts suggest that all but one lie above z ∼ 3. These four high-redshift (z > 3) galaxies have = 3.9, SFRs ∼ 400–1200 M⊙ yr−1, and Mdust ∼ 109.5M⊙. They provide a relatively complete selection (∼66%) of the most luminous (LIR > 1012.6L⊙) and highest-redshift (z > 3) galaxies detected within our survey area by AzTEC at 1.1 mm. We thus conclude that 2 mm surveys favor the selection of massive, vigorously star-forming, high-redshift galaxies. This is corroborated by GISMO-C4, a source with a low false-detection probability (∼6.2%), for which the absence of a (sub)millimeter counterpart supports a high-redshift origin (z ≳ 3). [ABSTRACT FROM AUTHOR]

To better constrain the physical mechanisms driving star formation, we present the first systematic study of the radio continuum size evolution of star-forming galaxies (SFGs) over the redshift range 0.35 <  z <  2.25. We use the VLA COSMOS 3 GHz map (noise rms = 2.3 μJy beam−1, θbeam = 0.75 arcsec) to construct a mass-complete sample of 3184 radio-selected SFGs that reside on and above the main sequence (MS) of SFGs. We constrain the overall extent of star formation activity in galaxies by applying a 2D Gaussian model to their radio continuum emission. Extensive Monte Carlo simulations are used to validate the robustness of our measurements and characterize the selection function. We find no clear dependence between the radio size and stellar mass, M⋆, of SFGs with 10.5 ≲ log(M⋆/M⊙) ≲ 11.5. Our analysis suggests that MS galaxies are preferentially extended, while SFGs above the MS are always compact. The median effective radius of SFGs on (above) the MS of Reff = 1.5 ± 0.2 (1.0 ± 0.2) kpc remains nearly constant with cosmic time; a parametrization of the form Reff ∝ (1 + z)α yields a shallow slope of only α = −0.26 ± 0.08 (0.12 ± 0.14) for SFGs on (above) the MS. The size of the stellar component of galaxies is larger than the extent of the radio continuum emission by a factor ∼2 (1.3) at z = 0.5 (2), indicating star formation is enhanced at small radii. The galactic-averaged star formation rate surface density (ΣSFR) scales with the distance to the MS, except for a fraction of MS galaxies (≲10%) that harbor starburst-like ΣSFR. These "hidden" starbursts might have experienced a compaction phase due to disk instability and/or a merger-driven burst of star formation, which may or may not significantly offset a galaxy from the MS. We thus propose to use ΣSFR and distance to the MS in conjunction to better identify the galaxy population undergoing a starbursting phase. [ABSTRACT FROM AUTHOR]

Exploring how radio-emitting active galactic nuclei (AGNs) behave and evolve with time is critical for understanding how AGN feedback impacts galaxy evolution. In this work, we investigate the relationship between 1.4 GHz radio continuum AGN luminosity (⁠|$L^{\rm AGN}_{\rm 1.4}$|⁠), specific black hole accretion rate (s-BHAR, defined as the accretion luminosity relative to the galaxy stellar mass), and redshift, for a luminosity-complete sample of radio-selected AGNs in the VLA COSMOS 3 GHz Large Project. The sample was originally selected from radio-continuum observations at 3 GHz, and includes about 1800 radio AGNs identified via (>2 σ) radio-excess relative to the infrared-radio correlation of star-forming galaxies. We further select a subsample of over 1200 radio AGNs that is complete in |$L^{\rm AGN}_{\rm 1.4}$| over different redshift ranges, out to |$z$| ∼ 4, and use X-ray stacking to calculate the average s-BHAR in each |$L^{\rm AGN}_{\rm 1.4}$| – |$z$| bin. We find that the average s-BHAR is independent of |$L^{\rm AGN}_{\rm 1.4}$|⁠, at all redshifts. However, we see a strong increase of s-BHAR with redshift, at fixed |$L^{\rm AGN}_{\rm 1.4}$|⁠. This trend resembles the strong increase in the fraction of star-forming host galaxies [based on the (NUV − r)/(r − J) colours] with redshift, at fixed |$L^{\rm AGN}_{\rm 1.4}$|⁠. A possible explanation for this similarity might imply a link between average AGN radiative power and availability of cold gas supply within the host galaxy. This study corroborates the idea that radio-selected AGNs become more radiatively efficient towards earlier epochs, independently of their radio power. [ABSTRACT FROM AUTHOR]

We present ALMA Band 9 observations of the [C ii ]158 |$\mu$| m emission for a sample of 10 main-sequence galaxies at redshift |$z$| ∼ 2, with typical stellar masses (log M ⋆/M⊙∼ 10.0–10.9) and star formation rates (∼35–115 M⊙yr−1). Given the strong and well-understood evolution of the interstellar medium from the present to |$z$| = 2, we investigate the behaviour of the [C ii ] emission and empirically identify its primary driver. We detect [C ii ] from six galaxies (four secure and two tentative) and estimate ensemble averages including non-detections. The [C ii ]-to-infrared luminosity ratio (⁠|${\rm [C\, {\small II}]}$| / L IR) of our sample is similar to that of local main-sequence galaxies (∼2 × 10−3), and ∼10 times higher than that of starbursts. The [C ii ] emission has an average spatial extent of 4–7 kpc, consistent with the optical size. Complementing our sample with literature data, we find that the [C ii ] luminosity correlates with galaxies' molecular gas mass, with a mean absolute deviation of 0.2 dex and without evident systematics: the [C ii ]-to-H2conversion factor (⁠|$\alpha _{\rm [C\, {\small II}]} \sim 30$| M⊙/L⊙) is largely independent of galaxies' depletion time, metallicity, and redshift. [C ii ] seems therefore a convenient tracer to estimate galaxies' molecular gas content regardless of their starburst or main-sequence nature, and extending to metal-poor galaxies at low and high redshifts. The dearth of [C ii ] emission reported for |$z$| > 6–7 galaxies might suggest either a high star formation efficiency or a small fraction of ultraviolet light from star formation reprocessed by dust. [ABSTRACT FROM AUTHOR]

We studied the molecular gas properties of AzTEC/C159, a star-forming disk galaxy at z = 4.567, in order to better constrain the nature of the high-redshift end of the submillimeter-selected galaxy (SMG) population. We secured 12CO molecular line detections for the J = 2 →1 and J = 5 →4 transitions using the Karl G. Jansky Very Large Array (VLA) and the NOrthern Extended Millimeter Array (NOEMA) interferometer. The broad (FWHM ~ 750 km s−1) and tentative double-peaked profiles of the two 12CO lines are consistent with an extended molecular gas reservoir, which is distributed in a rotating disk, as previously revealed from [CII] 158 μm line observations. Based on the 12CO(2 →1) emission line, we derived L′CO=(3.4±0.6)×1010 K km s−1 pc2, which yields a molecular gas mass of MH2(αCO/4.3)=(1.5±0.3)×1011 M⊙ and unveils a gas-rich system with μgas(αCO/4.3)≡MH2/M⋆=3.3±0.7. The extreme star formation efficiency of AzTEC/C159, parametrized by the ratio LIR/L′CO=(216±80) L⊙ (K km s−1 pc2)−1, is comparable to merger-driven starbursts such as local ultra-luminous infrared galaxies and SMGs. Likewise, the 12CO(5 →4)/CO(2 →1) line brightness temperature ratio of r52 = 0.55 ± 0.15 is consistent with high-excitation conditions as observed in SMGs. Based on mass budget considerations, we constrained the value for the L′CO – H2 mass conversion factor in AzTEC/C159, that is, αCO=3.9−1.3+2.7 M⊙ K−1 km−1 s pc−2, which is consistent with a self-gravitating molecular gas distribution as observed in local star-forming disk galaxies. Cold gas streams from cosmological filaments might be fueling a gravitationally unstable gas-rich disk in AzTEC/C159, which breaks into giant clumps and forms stars as efficiently as in merger-driven systems and generates high gas excitation. These results support the evolutionary connection between AzTEC/C159-like systems and massive quiescent disk galaxies at z ~ 2. [ABSTRACT FROM AUTHOR]

We imaged, with ALMA and ARGOS/LUCI, the molecular gas and dust and stellar continuum in XID2028, which is an obscured quasi-stellar object (QSO) at z = 1.593, where the presence of a massive outflow in the ionised gas component traced by the [OIII]5007 emission has been resolved up to 10 kpc. This target represents a unique test case to study QSO feedback in action at the peak epoch of AGN-galaxy co-evolution. The QSO was detected in the CO(5 − 4) transition and in the 1.3 mm continuum at ∼30 and ∼20σ significance, respectively; both emissions are confined in the central (<2 kpc) radius area. Our analysis suggests the presence of a fast rotating molecular disc (v ∼ 400 km s−1) on very compact scales well inside the galaxy extent seen in the rest-frame optical light (∼10 kpc, as inferred from the LUCI data). Adding available measurements in additional two CO transitions, CO(2 − 1) and CO(3 − 2), we could derive a total gas mass of ∼1010 M⊙, thanks to a critical assessment of CO excitation and the comparison with the Rayleigh– Jeans continuum estimate. This translates into a very low gas fraction (<5%) and depletion timescales of 40–75 Myr, reinforcing the result of atypical gas consumption conditions in XID2028, possibly because of feedback effects on the host galaxy. Finally, we also detect the presence of high velocity CO gas at ∼5σ, which we interpret as a signature of galaxy-scale molecular outflow that is spatially coincident with the ionised gas outflow. XID2028 therefore represents a unique case in which the measurement of total outflowing mass, of ∼500–800 M⊙ yr−1 including the molecular and atomic components in both the ionised and neutral phases, was attempted for a high-z QSO. [ABSTRACT FROM AUTHOR]

We present results on the dust attenuation of galaxies at redshift ∼3-6 by studying the relationship between the UV spectral slope (βUV) and the infrared excess (IRX; LIR/LUV) using Atacama Large Millimeter/submillimeter Array (ALMA) far-infrared continuum observations. Our study is based on a sample of 67 massive, star-forming galaxies with a median mass of M∼ ∼ 1010.7 M☉ spanning a redshift range z = 2.6-3.7 (median z = 3.2) that were observed with ALMA at λrest = 300 μm. Both the individual ALMA detections (41 sources) and stacks including all galaxies show the IRX-βUV relationship at z ∼ 3 is mostly consistent with that of local starburst galaxies on average. However, we find evidence for a large dispersion around the mean relationship by up to ±0.5 dex. Nevertheless, the locally calibrated dust correction factors based on the IRX-βUV relation are on average applicable to main-sequence z ∼ 3 galaxies. This does not appear to be the case at even higher redshifts, however. Using public ALMA observations of z ∼ 4-6 galaxies we find evidence for a significant evolution in the IRX-βUV and the IRX-M* relations beyond z ∼ 3 towards lower IRX values. We discuss several caveats that could affect these results, including the assumed dust temperature. ALMA observations of larger z > 3 galaxy sample spanning a wide range of physical parameters (e.g. lower stellar mass) will be important to investigate this intriguing redshift evolution further. [ABSTRACT FROM AUTHOR]

We present deep ALMA CO(5-4) observations of a main-sequence, clumpy galaxy at z = 1.5 in the HUDF. Thanks to the ∼0″.5 resolution of the ALMA data, we can link stellar population properties to the CO(5-4) emission on scales of a few kiloparsec. We detect strong CO(5-4) emission from the nuclear region of the galaxy, consistent with the observed LIR-L'CO(5-4) correlation and indicating ongoing nuclear star formation. The CO(5-4) gas component appears more concentrated than other star formation tracers or the dust distribution in this galaxy. We discuss possible implications of this difference in terms of star formation efficiency and mass build-up at the galaxy centre. Conversely, we do not detect any CO(5-4) emission from the UV-bright clumps. This might imply that clumps have a high star formation efficiency (although they do not display unusually high specific star formation rates) and are not entirely gas dominated, with gas fractions no larger than that of their host galaxy (∼50 per cent). Stellar feedback and disc instability torques funnelling gas towards the galaxy centre could contribute to the relatively low gas content. Alternatively, clumps could fall in a more standard star formation efficiency regime if their actual star formation rates are lower than generally assumed. We find that clump star formation rates derived with several different, plausible methods can vary by up to an order of magnitude. The lowest estimates would be compatible with a CO(5-4) non-detection even for main-sequence like values of star formation efficiency and gas content. [ABSTRACT FROM AUTHOR]

Similarly to the cosmic star formation history, the black hole accretion rate density of the Universe peaked at 199 per cent probability of lower depletion time-scales and lower molecular gas fractions in AGN hosts with respect to the non-AGN comparison sample. We discuss the implications of these observations on the impact that AGN feedback may have on star formation efficiency of z >1 galaxies. [ABSTRACT FROM AUTHOR]

e present millimetre dust emission measurements of two Lyman-break galaxies at z ∼ 3 and construct for the first time fully sampled infrared spectral energy distributions (SEDs), from mid-IR to the Rayleigh-Jeans tail, of individually detected, unlensed, UV-selected, main sequence (MS) galaxies at z = 3. The SED modelling of the two sources confirms previous findings, based on stacked ensembles, of an increasing mean radiation field hUi with redshift, consistent with a rapidly decreasing gas metallicity in z > 2 galaxies. Complementing our study with CO[J = 3 → 2] emission line observations, we have measured the molecular gas mass reservoir (MH2 ) of the systems using three independent approaches: 1) CO line observations; 2) the dust to gas mass ratio vs. metallicity relation; and 3) a single band, dust emission flux on the Rayleigh-Jeans side of the SED. All techniques return consistent MH2 estimates within a factor of two or less, yielding gas depletion time-scales (τdep ≈ 0.35 Gyr) and gas-to-stellar mass ratios (MH2 /M∗ ≈ 0.5−1) for our z ∼ 3 massive MS galaxies. The overall properties of our galaxies are consistent with trends and relations established at lower redshifts, extending the apparent uniformity of star-forming galaxies over the last 11.5 billion years. [ABSTRACT FROM AUTHOR]

We make use of the deep Karl G. Jansky Very Large Array (VLA) COSMOS radio observations at 3 GHz to infer radio luminosity functions of star-forming galaxies up to redshifts of z ~ 5 based on approximately 6000 detections with reliable optical counterparts. This is currently the largest radio-selected sample available out to z ~ 5 across an area of 2 square degrees with a sensitivity of rms ≈2:3 μJy beam-1. By fixing the faint and bright end shape of the radio luminosity function to the local values, we find a strong redshift trend that can be fitted with a pure luminosity evolution L1.4 GHz ∝ (1 + z)(3:16±0:2)-(0:32±0:07)z. We estimate star formation rates (SFRs) from our radio luminosities using an infrared (IR)-radio correlation that is redshift dependent. By integrating the parametric fits of the evolved luminosity function we calculate the cosmic SFR density (SFRD) history since z ~ 5. Our data suggest that the SFRD history peaks between 2 < z < 3 and that the ultraluminous infrared galaxies (100 M⊙ yr-1 < SFR < 1000 M⊙ yr-1) contribute up to ~25% to the total SFRD in the same redshift range. Hyperluminous infrared galaxies (SFR > 1000 M⊙ yr-1) contribute an additional ≲2% in the entire observed redshift range. We find evidence of a potential underestimation of SFRD based on ultraviolet (UV) rest-frame observations of Lyman break galaxies at high redshifts (z & 4) on the order of 15-20%, owing to appreciable star formation in highly dust-obscured galaxies, which might remain undetected in such UV observations. [ABSTRACT FROM AUTHOR]

We examine the behaviour of the infrared-radio correlation (IRRC) over the range 0 < z ≲ 6 using new, highly sensitive 3 GHz observations with the Karl G. Jansky Very Large Array (VLA) and infrared data from the Herschel Space Observatory in the 2 deg2 COSMOS field. We distinguish between objects where emission is believed to arise solely from star-formation, and those where an active galactic nucleus (AGN) is thought to be present. We account for non-detections in the radio or in the infrared using a doublycensored survival analysis. We find that the IRRC of star-forming galaxies, quantified by the infrared-to-1.4 GHz radio luminosity ratio (qTIR), decreases with increasing redshift: qTIR(z) = (2:88 ± 0:03)(1 + z)-0:19±0:01. This is consistent with several previous results from the literature. Moderate-to-high radiative luminosity AGN do not follow the same qTIR(z) trend as star-forming galaxies, having a lower normalisation and steeper decrease with redshift. We cannot rule out the possibility that unidentified AGN contributions only to the radio regime may be steepening the observed qTIR(z) trend of the star-forming galaxy population. We demonstrate that the choice of the average radio spectral index directly affects the normalisation, as well as the derived trend with redshift of the IRRC. An increasing fractional contribution to the observed 3 GHz flux by free-free emission of star-forming galaxies may also affect the derived evolution. However, we find that the standard (M82-based) assumption of the typical radio spectral energy distribution (SED) for star-forming galaxies is inconsistent with our results. This suggests a more complex shape of the typical radio SED for star-forming galaxies, and that imperfect K corrections in the radio may govern the derived trend of decreasing qTIR with increasing redshift. A more detailed understanding of the radio spectrum is therefore required for robust K corrections in the radio and to fully understand the cosmic evolution of the IRRC. Lastly, we present a redshift-dependent relation between rest-frame 1.4 GHz radio luminosity and star formation rate taking the derived redshift trend into account. [ABSTRACT FROM AUTHOR]

We investigate the evolution of the galaxy star formation rate function (SFRF) and cosmic star formation rate density (CSFRD) of z ~ 1-4 galaxies, using cosmological smoothed particle hydrodynamic (SPH) simulations and a compilation of ultraviolet (UV), infrared (IR) and Ha observations. These tracers represent different populations of galaxies with the IR light being a probe of objects with high star formation rates and dust contents, while UV and Ha observations provide a census of low star formation galaxies where mild obscuration occurs. We compare the above SFRFs with the results of SPH simulations run with the code P-GADGET3(XXL). We focus on the role of feedback from active galactic nuclei (AGN) and supernovae in form of galactic winds. The AGN feedback prescription that we use decreases the simulated CSFRD at z < 3 but is not sufficient to reproduce the observed evolution at higher redshifts. We explore different wind models and find that the key factor for reproducing the evolution of the observed SFRF and CSFRD at z ~ 1-4 is the presence of a feedback prescription that is prominent at high redshifts (z = 4) and becomes less efficient with time. We show that variable galactic winds which are efficient at decreasing the SFRs of low-mass objects are quite successful in reproducing the observables. [ABSTRACT FROM AUTHOR]

The article presents a case study of a three-month-old male infant with severe hemophilia A, who was admitted with poor feeding, abdominal distension, and irritability for 48 hours. The infant undergone a surgical review for the assessment of intestinal obstruction or an ileus. He was screened using spinal ultrasound in screening for spinal hematoma.

We have developed a new prior-based source extraction tool, XID+, to carry out photometry in the Herschel SPIRE (Spectral and Photometric Imaging Receiver) maps at the positions of known sources. XID+ is developed using a probabilistic Bayesian framework that provides a natural framework in which to include prior information, and uses the Bayesian inference tool Stan to obtain the full posterior probability distribution on flux estimates. In this paper, we discuss the details of XID+ and demonstrate the basic capabilities and performance by running it on simulated SPIRE maps resembling the COSMOS field, and comparing to the current prior-based source extraction tool DESPHOT. Not only we show that XID+ performs better on metrics such as flux accuracy and flux uncertainty accuracy, but we also illustrate how obtaining the posterior probability distribution can help overcome some of the issues inherent with maximum-likelihood-based source extraction routines. We run XID+ on the COSMOS SPIRE maps from Herschel Multi-Tiered Extragalactic Survey using a 24-µm catalogue as a positional prior, and a uniform flux prior ranging from 0.01 to 1000 mJy. We show the marginalized SPIRE colour--colour plot and marginalized contribution to the cosmic infrared background at the SPIRE wavelengths. XID+ is a core tool arising from the Herschel Extragalactic Legacy Project (HELP) and we discuss how additional work within HELP providing prior information on fluxes can and will be utilized. The software is available at https://github.com/H-E-L-P/XID_plus.We also provide the data product for COSMOS. We believe this is the first time that the full posterior probability of galaxy photometry has been provided as a data product. [ABSTRACT FROM AUTHOR]

The Herschel Extragalactic Legacy Project (HELP) brings together a vast range of data from many astronomical observatories. Its main focus is on the Herschel data, which maps dustobscured star formation over 1300 deg². With this unprecedented combination of data sets, it is possible to investigate how the star formation versus stellar mass relation (main sequence) of star-forming galaxies depends on environment. In this pilot study, we explore this question within 0.1 2. We also estimate the evolution of the star formation rate density in the COSMOS field, and our results are consistent with previous measurements at z < 1.5 and z > 2 but we find a 1.4+0.3-0.2 times higher peak value of the star formation rate density at z ~ 1.9. [ABSTRACT FROM AUTHOR]

Background Proton pump inhibitor ( PPI) use is associated with an increased risk of Clostridium difficile infection ( CDI), though the mechanism is unclear. PPI induced alterations to the gut microbiome may facilitate the emergence of CDI, though the effects of PPIs on gut microbiota are not well characterised. [Correction added on 10 March 2016, after first online publication: microflora has been changed to microbiota throughout the article.] Aim To compare the faecal microbiomes of long-term PPI users to those with no history of PPI use. Methods We used a population-based database to identify individuals with ≥5 years of continuous PPI use along with non- PPI using controls. Stool samples were subjected to microbiological analysis, with hierarchical clustering at genus level, along with alpha and beta diversity measures comparing the two groups. Metadata was accounted for using quantile regression to eliminate potential confounding variables in taxonomic abundance comparisons. Results Sixty-one subjects (32 PPI, 29 controls) were analysed. While no significant differences in alpha diversity were found between the PPI users and controls, a moderate shift of the PPI users away from the non- PPI user cluster in the beta diversity was observed. After controlling for pertinent confounders, we discovered a decrease in Bacteroidetes and an increase in Firmicutes at the phylum level. We also performed species classifications and found Holdemania filiformis and Pseudoflavonifractor capillosus to be increased and decreased in the PPI cohort, respectively. Conclusions Long-term PPIs use has an effect on the gut microbiome. The alteration in the ratio of Firmicutes to Bacteroidetes may pre-dispose to the development of CDI. [ABSTRACT FROM AUTHOR]

We study the properties of satellites in the environment of massive star-forming galaxies at z ~ 1.8 in the COSMOS field, using a sample of 215 galaxies on the main sequence of star formation with an average mass of ~1011 M⊙. At z > 1.5, these galaxies typically trace halos of mass ≲1013 M⊙. We use optical-near-infrared photometry to estimate stellar masses and star formation rates (SFR) of centrals and satellites down to ~6 x 109 M⊙. We stack data around 215 central galaxies to statistically detect their satellite halos, finding an average of ~3 galaxies in excess of the background density. We fit the radial profiles of satellites with simple β-models, and compare their integrated properties to model predictions. We find that the total stellar mass of satellites amounts to ~68% of the central galaxy, while spectral energy distribution modeling and far-infrared photometry consistently show their total SFR to be 25-35% of the central's rate. We also see significant variation in the specific SFR of satellites within the halo with, in particular, a sharp decrease at <100 kpc. After considering different potential explanations, we conclude that this is likely an environmental signature of the hot inner halo. This effect can be explained in the first order by a simple free-fall scenario, suggesting that these low-mass environments can shut down star formation in satellites on relatively short timescales of ~0.3 Gyr. [ABSTRACT FROM AUTHOR]

Aims. Gas outflows are believed to play a pivotal role in shaping galaxies, as they regulate both star formation and black hole growth. Despite their ubiquitous presence, the origin and the acceleration mechanism of these powerful and extended winds is not yet understood. Direct observations of the cold gas component in objects with detected outflows at other wavelengths are needed to assess the impact of the outflow on the host galaxy interstellar medium (ISM). Methods. We observed with the Plateau de Bure Interferometer an obscured quasar at z ~ 1:5, XID2028, for which the presence of an ionized outflow has been unambiguously signalled by NIR spectroscopy. The detection of 12CO(3-2) emission in this source allows us to infer the molecular gas content and compare it to the ISM mass derived from the dust emission. We then analyzed the results in the context of recent insights on scaling relations, which describe the gas content of the overall population of star-forming galaxies at a similar redshifts. Results. The star formation effciency (~100) and gas mass (Mgas = 2:1-9:5 × 1010 MΘ) inferred from the CO(3-2) line depend on the underlying assumptions on the excitation of the transition and the CO-to-H2 conversion factor. However, the combination of this information and the ISM mass estimated from the dust mass suggests that the ISM/gas content of XID2028 is significantly lower than expected for its observed M*, sSFR and redshift, based on the most up-to-date calibrations (with gas fraction <20% and depletion timescale <340 Myr). Conclusions. Overall, the constraints we obtain from the far infrared and millimeter data suggest that we are observing QSO feedback able to remove the gas from the host. [ABSTRACT FROM AUTHOR]

We investigate the CO excitation of normal (near-IR selected BzK) star-forming (SF) disk galaxies at z = 1.5 using IRAM Plateau de Bure observations of the CO[2-1], CO[3-2], and CO[5-4] transitions for four galaxies, including VLA observations of CO[1-0] for three of them, with the aim of constraining the average state of H2 gas. By exploiting previous knowledge of the velocity range, spatial extent, and size of the CO emission, we measure reliable line fluxes with a signal-to-noise ratio >4-7 for individual transitions. While the average CO spectral line energy distribution (SLED) has a subthermal excitation similar to the Milky Way (MW) up to CO[3-2], we show that the average CO[5-4] emission is four times stronger than assuming MW excitation. This demonstrates that there is an additional component of more excited, denser, and possibly warmer molecular gas. The ratio of CO[5-4] to lower-J CO emission is lower than in local (ultra-)luminous infrared galaxies (ULIRGs) and high-redshift starbursting submillimeter galaxies, however, and appears to be closely correlated with the average intensity of the radiation field (U) and with the star formation surface density, but not with the star formation efficiency. The luminosity of the CO[5-4] transition is found to be linearly correlated with the bolometric infrared luminosity over four orders of magnitudes. For this transition, z = 1.5 BzK galaxies follow the same linear trend as local spirals and (U)LIRGs and high-redshift star-bursting submillimeter galaxies. The CO[5-4] luminosity is thus empirically related to the dense gas and might be a more convenient way to probe it than standard high-density tracers that are much fainter than CO. We see excitation variations among our sample galaxies that can be linked to their evolutionary state and clumpiness in optical rest-frame images. In one galaxy we see spatially resolved excitation variations, where the more highly excited part of the galaxy corresponds to the location of massive SF clumps. This provides support to models that suggest that giant clumps are the main source of the high-excitation CO emission in high-redshift disk-like galaxies. [ABSTRACT FROM AUTHOR]