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Studies investigating the relationship between AGN power and the star formation rates (SFRs) of their host galaxies often rely on averaging techniques -- such as stacking -- to incorporate information from non-detections. However, averages, and especially means, can be strongly affected by outliers and can therefore give a misleading indication of the "typical" case. Recently, a number of studies have taken a step further by binning their sample in terms of AGN power (approximated by the 2-10keV luminosity of the AGN), and investigating how the SFR distribution differs between these bins. These bin thresholds are often weakly motivated, and binning implicitly assumes that sources within the same bin have similar (or even identical) properties. In this paper, we investigate whether the distribution of host SFRs -- relative to the locus of the star-forming main sequence (i.e., $R_{\rm MS}$) -- changes continuously as a function of AGN power. We achieve this by using a hierarchical Bayesian model that completely removes the need to bin in AGN power. In doing so, we find strong evidence that the $R_{\rm MS}$ distribution changes with 2-10keV X-ray luminosity. The results suggest that higher X_ray luminosity AGNs have a tighter physical connection to the star-forming process than lower X-ray luminosity AGNs, at least within the $0.8 < z < 1.2$ redshift range considered here., 12 pages, 4 figures, accepted for publication in MNRAS

Salt marshes are important sites of nitrogen cycling and removal that straddle the land/ocean interface, allowing them to intercept human-derived nitrogen before it reaches coastal waters where it causes problems like hypoxia and harmful algal blooms. In 2010, the Deepwater Horizon oil spill released an estimated five million barrels of crude oil into the Gulf of Mexico, significantly contaminating coastal wetlands over approximately 800 km of shoreline. We investigated microbial nitrogen cycling processes in soil from four salt marshes in Terrebonne Bay, Louisiana, USA that were either exposed or not exposed to Deepwater Horizon oil over the course of 1 year (2013–2014), 2.5–3.5 years post-spill. Specifically, we measured nitrification and denitrification potentials, nitrogen cycling functional gene abundances (nirS, bacterial and archaeal amoA), and soil physical and chemical properties. We show that variation in nitrification and denitrification potentials was independent of site oil exposure. Large year-to-year differences in springtime nitrification potentials were inversely related to plant live belowground biomass, indicating that competition for nitrogen is likely an important control on nitrification. There were positive correlations between nitrification potentials and both soil extractable nitrate concentrations and denitrification potentials, supporting the idea that denitrification is coupled with nitrification. We found no evidence that there was a long-term impact of oil exposure on salt marsh soil microbial nitrogen cycling processes and the nitrogen removal ecosystem service they provide. It is important to note, however, that these impacts could have been masked by high background variability in process rates or loss of oil exposed soil to coastal erosion.

The far-IR/sub-mm wavelength range contains a wealth of diagnostic information that is important for understanding the role of radio AGN in galaxy evolution. Here we present the results of Herschel PACS and SPIRE observations of a complete sample of 46 powerful 2Jy radio AGN at intermediate redshifts (0.05 < z < 0.7), which represent the deepest pointed observations of a major sample of radio AGN undertaken by Herschel. In order to assess the importance of non-thermal synchrotron emission at far-IR wavelengths, we also present new APEX sub-mm and ALMA mm data. We find that the overall incidence of non-thermal contamination in the PACS bands ($ $200$μ$m) sampled by the SPIRE instrument. Non-thermal contamination is strongest in objects with compact CSS/GPS or extended FRI radio morphologies, and in those with type 1 optical spectra. Considering thermal dust emission, we find strong correlations between the 100 and 160$μ$m monochromatic luminosities and AGN power indicators, providing further evidence that radiation from the AGN may be an important heating source for the far-IR emitting dust. Clearly, AGN contamination -- whether by the direct emission from synchrotron-emitting lobes and cores, or via radiative heating of the cool dust -- needs to be carefully considered when using the far-IR continuum to measure the star formation rates in the host galaxies of radio AGN., 22 pages, 8 figures, Accepted in MNRAS

Ultrarelativistic collisions of heavy atomic nuclei produce an extremely hot and dense phase of matter, known as quark–gluon plasma (QGP), which behaves like a near-perfect fluid with the smallest specific shear viscosity—the ratio of the shear viscosity to the entropy density—of any known substance1. Due to its transience (lifetime ~ 10−23 s) and microscopic size (10−14 m), the QGP cannot be observed directly, but only through the particles it emits; however, its characteristics can be inferred by matching the output of computational collision models to experimental observations. Previous work, using viscous relativistic hydrodynamics to simulate QGP, has achieved semiquantitative constraints on key physical properties, such as its specific shear and bulk viscosity, but with large, poorly defined uncertainties2–8. Here, we present the most precise estimates so far of QGP properties, including their quantitative uncertainties. By applying established Bayesian parameter estimation methods9 to a dynamical collision model and a wide variety of experimental data, we extract estimates of the temperature-dependent specific shear and bulk viscosity simultaneously with related initial-condition properties. The method is extensible to other collision models and experimental data and may be used to characterize additional aspects of high-energy nuclear collisions. As the quark–gluon plasma is a short-lived state of matter, its properties cannot be measured directly. A Bayesian parameter estimation method now provides a reliable estimation of the temperature-dependent specific shear and bulk viscosities.

Few studies have focused on broad scale biogeographic patterns of ammonia oxidizers in coastal systems, yet understanding the processes that govern them is paramount to understanding the mechanisms that drive biodiversity, and ultimately impact ecosystem processes. Here we present a meta-analysis of 16 years of data of ammonia oxidizer abundance, diversity, and activity in New England (NE) salt marshes and 5 years of data from marshes in the Gulf of Mexico (GoM). Potential nitrification rates were more than 80x higher in GoM compared to NE marshes. However, nitrifier abundances varied between regions, with ammonia-oxidizing archaea (AOA) and comammox bacteria significantly greater in GoM, while ammonia-oxidizing bacteria (AOB) were more than 20x higher in NE than GoM. Total bacterial 16S rRNA genes were also significantly greater in GoM marshes. Correlation analyses of rates and abundance suggest that AOA and comammox are more important in GoM marshes, whereas AOB are more important in NE marshes. Furthermore, ratios of nitrifiers to total bacteria in NE were as much as 80x higher than in the GoM, suggesting differences in the relative importance of nitrifiers between these systems. Communities of AOA and AOB were also significantly different between the two regions, based on amoA sequences and DNA fingerprints (terminal restriction fragment length polymorphism). Differences in rates and abundances may be due to differences in salinity, temperature, and N loading between the regions, and suggest significantly different N cycling dynamics in GoM and NE marshes that are likely driven by strong environmental differences between the regions.

Measuring the star-forming properties of AGN hosts is key to our understanding of galaxy formation and evolution. However, this topic remains debated, partly due to the difficulties in separating the infrared (i.e. 1--1000 $\mu$m) emission into AGN and star-forming components. Taking advantage of archival far-infrared data from Herschel, we present a new set of AGN and galaxy infrared templates, and introduce the spectral energy distribution fitting code IRAGNSEP. Both can be used to measure infrared host galaxy properties, free of AGN contamination. To build these, we used a sample of 100 local ($z$ < 0.3), low-to-high luminosity AGNs (i.e. $L_{\rm bol}~\sim~10^{42--46}~\rm erg~s^{-1}$), selected from the 105-month Swift - BAT X-ray survey, which have archival Spitzer - IRS spectra and Herschel photometry. We first built a set of seven galaxy templates using a sample of 55 star-forming galaxies selected via infrared diagnostics. Using these templates, combined with a flexible model for the AGN contribution, we extracted the intrinsic infrared emission of our AGN sample. We further demonstrate that we can reduce the diversity in the intrinsic shapes of AGN spectral energy distributions down to a set of three AGN templates, of which two represent AGN continuum, and one represents silicate emission. Our results indicate that, on average, the contribution of AGNs to the far-infrared ($\lambda~\gtrsim$ 50 $\mu$m) is not as high as suggested by some recent work. We further show that the need for two infrared AGN continuum templates could be related to nuclear obscuration, where one of our templates appears dominated by the emission of the extended polar dust., Comment: 20 pages (38 pages including appendices), 19 figures, 6 tables, Accepted for publication in MNRAS

BackgroundMedical cares guidelines for lumbosciatics pains are well codified in several country: NSAIDs, analgesics and physical therapy associated, at physician’s discretion, to lumbar epidural infiltrations.Lumbar mechanical tractions have not a clear identified place in the lumbosciatic pain treatment. It is empirically realized in France’s several medical centers.However, no current literature studies have shown a significant efficacity of lumbar mechanicals tractions in this indication. Most of the time, studies presented a lack of power or methodological bias. (1,2)ObjectivesThe aim of this study is to demonstrate the superiority of lumbar traction associated with standard treatment (epidural injections, analgesics, NSAID) compared to medical treatment alone in lombosciatics pains of discal origin.MethodsWe performed a monocentric interventional prospective superiority study from 2013 to 2021, randomized controlled in the rheumatology unit of Reims University Hospital. Patients included had to present a lumboradicular pain, with a concordant discal hernia on MRI or scanner, and to be naive of any lumbar surgery. We recorded demographical and clinical data at baseline and during the follow up. After their consent, patients were randomized between the traction group and the medical group. The medical group received the standard treatment (NSAIDs, analgesics) associated with at least 2 epidural infiltrations. The traction group received the standard treatment, infiltrations and at least 3 lumbar tractions. Treatment was considered as effective if there was a pain diminution at least 25 % between baseline and at 1 month. Patients were assessed on their pain at baseline, at 1 month and at 3 months of their treatment. Pain was assessed using a visual analog scale on lumbar and radicular localisation.Superiority analysis has been performed by using the Chi-2 test.ResultsFour Hundred twenty-eight patients were included: 207 patients in the lumbar traction group, 210 patients in the medical treatment alone group and 11 patients with missing data. The male/female sex ratio was 1.39:1. The patients suffered from 49.52% (205 patients) right and 50.48% (209 patients) left lumboradiculalgia, mostly L5 (41% or 172 patients) and S1 (50% or 207 patients).The pains evaluation at one month was recorded for 377 patients: 190 in traction group (50.3%) and 187 in medical group (49.7%). Two hundred twelve/377 (56.2%) patients had a pain reduction of at least 25 % at one month: 117/377 patients in tractions group (31%) and 95/377 in medical group (25%).Twenty/377 patients (5%) were operated on before the one-month recall. Therefore, patients treated with lumbar traction had a significant reduction in pain (p=0.036) compared to patients with medical treatment alone.ConclusionThis study is one of the first randomized controlled studies highlighting the superiority of lumbar traction in combination with standard treatment compared to medical treatment alone.References[1]Chou R, Huffman LH. Nonpharmacologic Therapies for Acute and Chronic Low Back Pain: A Review of the Evidence for an American Pain Society/American College of Physicians Clinical Practice Guideline. Ann Intern Med. 2 oct 2007;147(7):492-504.[2]Wegner I, Widyahening IS, van Tulder MW, Blomberg SE, de Vet HC, Brønfort G, et al. Traction for low-back pain with or without sciatica. Cochrane Database Syst Rev. 19 août 2013;2013(8):CD003010.Disclosure of InterestsNone declared.

Background Osteonecrosis of the femoral head (ONFH) is a potentially severe toxicity associated with glucocorticoid treatment for pediatric hematologic malignancy. We examined clinical outcomes of THA in adolescents and young adults treated for hematologic malignancies who developed advanced ONFH. Methods In a single-institution cohort, we retrospectively reviewed medical records and imaging for perioperative complications, reoperations, functional assessment at last follow-up, and radiological outcomes. Twenty-seven patients (41 hips) underwent THA (bilateral in 14 patients). There were 11 males. Median (interquartile range [IQR]) age at primary diagnosis was 14.9 years [1.8-18.9]. The median (IQR) age at THA was 19.8 years [14.6-30.3]. Mean (range) post-THA follow-up was 111.5 months (65.4-165.8). Results Perioperative complications included one intraoperative calcar fracture that was secured with a cerclage wire and one posterior hip dislocation that occurred 6 days postoperatively, requiring closed reduction. One hip required a revision 21.1 months post-THA due to a fractured ceramic liner. The radiographic review was available for 38 of 41 hips and demonstrated none with loosening, subsidence, or osteolysis; nine developed periacetabular stress shielding. Incidence of stress shielding was associated with increased postoperative pain (P = .0130). There was a significant functional improvement in range of motion (ROM), pain, use of supports, participation in school, work, and sports, and use of pain medication from preoperative to postoperative clinical visits (P Discussion Total hip arthroplasty in adolescents and young adults offers symptomatic and functional improvement in patients with ONFH. We found it to be safe with low perioperative complication rates even in patients undergoing active treatment for malignancy. Level of Evidence Level IV, case series study. See Instructions for authors for a complete description of levels of evidence.

We posit a unified hydrodynamic and microscopic description of the quark-gluon plasma (QGP) produced in ultrarelativistic $p$-Pb and Pb-Pb collisions at $\sqrt{s_\mathrm{NN}}=5.02$ TeV and evaluate our assertion using Bayesian inference. Specifically, we model the dynamics of both collision systems using initial conditions with parametric nucleon substructure, a pre-equilibrium free-streaming stage, event-by-event viscous hydrodynamics, and a microscopic hadronic afterburner. Free parameters of the model which describe the initial state and QGP medium are then simultaneously calibrated to fit charged particle yields, mean $p_T$, and flow cumulants. We argue that the global agreement of the calibrated model with the experimental data strongly supports the existence of hydrodynamic flow in small collision systems at ultrarelativistic energies, and that the flow produced develops at length scales smaller than a single proton. Posterior estimates for the model's input parameters are obtained, and new insights into the temperature dependence of the QGP transport coefficients and event-by-event structure of the proton are discussed.

We present a new modeling of the X-ray luminosity function (XLF) of Active Galactic Nuclei (AGN) out to z$\sim$3, dissecting the contribution of main-sequence (MS) and starburst (SB) galaxies. For each galaxy population, we convolved the observed galaxy stellar mass (M$_{\star}$) function with a grid of M$_{\star}$-independent Eddington ratio ($\lambda_{\rm EDD}$) distributions, normalised via empirical black hole accretion rate (BHAR) to star formation rate (SFR) relations. Our simple approach yields an excellent agreement with the observed XLF since z$\sim$3. We find that the redshift evolution of the observed XLF can only be reproduced through an intrinsic flattening of the $\lambda_{\rm EDD}$ distribution, and with a positive shift of the break $\lambda^{*}$, consistent with an anti-hierarchical behavior. The AGN accretion history is predominantly made by massive (10$^{10}$44.36 + 1.28$\cdot$(1+z). We infer that the probability of finding highly-accreting ($\lambda_{\rm EDD}>$ 10%) AGN significantly increases with redshift, from 0.4% (3.0%) at z=0.5 to 6.5% (15.3%) at z=3 for MS (SB) galaxies, implying a longer AGN duty cycle in the early Universe. Our results strongly favor a M$_{\star}$-dependent ratio between BHAR and SFR, as BHAR/SFR $\propto$ M$_{\star}^{0.73[+0.22,-0.29]}$, supporting a non-linear BH buildup relative to the host. Finally, this framework opens potential questions on super-Eddington BH accretion and different $\lambda_{\rm EDD}$ prescriptions for understanding the cosmic BH mass assembly., Comment: Accepted for publication in ApJ. 25 pages, 15 figures, 2 tables. The best X-ray luminosity functions are available at https://github.com/idelvecchio/XLF_Delvecchio2020.git