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Restoration management of phosphorus pollution on lowland fen peatlands: A data evidence review from the Somerset Levels and Moors
Eutrophication of wetlands caused by urban, industrial and agricultural run-off is an important environmental problem. Eutrophication is characterized by excessive plant and algal growth due to the increased availability of one or more growth âlimiting nutrientsâ, in freshwater generally considered to be controlled by the bioavailability of phosphorus (P). The Somerset Levels and Moors (SLMs) catchments are subject to intensive agriculture and wastewater inputs which leads to nutrient contamination of the inflow waters, to the extent that they fail Water Framework Directive Good Status targets for P concentrations. In 2021, Natural England downgraded the status of the SLMs Sites of Special Scientific Interest (SSSIs) to âUnfavourable Decliningâ, owing to poor water quality, mostly associated with P concentrations and associated duckweed and filamentous algal blooms. Macro-plant nutrient concentrations were analysed in ditches, dipwells, soil, sediment and harvested plant biomass across a number of sites to provide an assessment of the overall apportionment of P inputs and reservoirs. Here we present a combined dataset of stores, fluxes and loadings of P. The data show large temporal and spatial changes in the concentrations of P and nitrogen (N) across the peat rich soils. We suggest how an altered hydrological regime and plant biomass harvesting could be used to reduce further eutrophication and how legacy P stored in the peat body could be mobilized by flooding and over time evacuated from the wetland. The findings suggest how paludiculture (wet agricultural crops) and rewetting of the peat body may help to restore the Ramsar wetland. We discuss how complex biogeochemical interactions occur during the rewetting process and how the need to export P via new land management mitigation measures should be balanced against requirements to maximise regulating and provisioning ecosystem services
A Serendipitous Galaxy Cluster Survey with XMM: Expected Catalogue Properties and Scientific Applications
This paper describes a serendipitous galaxy cluster survey that we plan to
conduct with the XMM X-ray satellite. We have modeled the expected properties
of such a survey for three different cosmological models, using an extended
Press-Schechter (Press & Schechter 1974) formalism, combined with a detailed
characterization of the expected capabilities of the EPIC camera on board XMM.
We estimate that, over the ten year design lifetime of XMM, the EPIC camera
will image a total of ~800 square degrees in fields suitable for the
serendipitous detection of clusters of galaxies. For the presently-favored
low-density model with a cosmological constant, our simulations predict that
this survey area would yield a catalogue of more than 8000 clusters, ranging
from poor to very rich systems, with around 750 detections above z=1. A
low-density open Universe yields similar numbers, though with a different
redshift distribution, while a critical-density Universe gives considerably
fewer clusters. This dependence of catalogue properties on cosmology means that
the proposed survey will place strong constraints on the values of Omega-Matter
and Omega-Lambda. The survey would also facilitate a variety of follow-up
projects, including the quantification of evolution in the cluster X-ray
luminosity-temperature relation, the study of high-redshift galaxies via
gravitational lensing, follow-up observations of the Sunyaev-Zel'dovich effect
and foreground analyses of cosmic microwave background maps.Comment: Accepted to ApJ. Minor changes, e.g. presentation of temperature
errors as a figure (rather than as a table). Latex (20 pages, 6 figures, uses
emulateapj.sty
Repression and 3D-restructuring resolves regulatory conflicts in evolutionarily rearranged genomes
Regulatory landscapes drive complex developmental gene expression, but it remains unclear how their integrity is maintained when incorporating novel genes and functions during evolution. Here, we investigated how a placental mammal-specific gene, Zfp42, emerged in an ancient vertebrate topologically associated domain (TAD) without adopting or disrupting the conserved expression of its gene, Fat1. In ESCs, physical TAD partitioning separates Zfp42 and Fat1 with distinct local enhancers that drive their independent expression. This separation is driven by chromatin activity and not CTCF/cohesin. In contrast, in embryonic limbs, inactive Zfp42 shares Fat1âs intact TAD without responding to active Fat1 enhancers. However, neither Fat1 enhancer-incompatibility nor nuclear envelope-attachment account for Zfp42âs unresponsiveness. Rather, Zfp42âs promoter is rendered inert to enhancers by context-dependent DNA methylation. Thus, diverse mechanisms enabled the integration of independent Zfp42 regulation in the Fat1 locus. Critically, such regulatory complexity appears common in evolution as, genome wide, most TADs contain multiple independently expressed genes.We thank the Montpellier Ressources Imagerie facility (BioCampus Montpellier, Centre National de la Recherche Scientifique [CNRS], INSERM, University of Montpellier) and for computer resources from CINECA (ISCRA grant thanks to computer resources from INFN and CINECA [ISCRA Grant HP10C8JWU7]). G.C., Q.S., and F.B. were supported by a grant from the European Research Council (Advanced Grant 3DEpi, 788972) and by the CNRS. This work was funded by EMBO and the Wellcome Trust (ALTF1554-2016 and 206475/Z/17/Z; to M.I.R.) as well as the Deutsche Forschungsgemeinschaft (KR3985/7-3 and MU 880/16-1 to S.M.)
Probing the Nature of High Redshift Weak Emission Line Quasars: A Young Quasar with a Starburst Host Galaxy
We present the discovery of PSO J083.8371+11.8482, a weak emission line
quasar with extreme star formation rate at . This quasar was selected
from Pan-STARRS1, UHS, and unWISE photometric data. Gemini/GNIRS spectroscopy
follow-up indicates a MgII-based black hole mass of
and an
Eddington ratio of , in line
with actively accreting supermassive black hole (SMBH) at . HST
imaging sets strong constraint on lens-boosting, showing no relevant effect on
the apparent emission. The quasar is also observed as a pure point-source with
no additional emission component. The broad line region (BLR) emission is
intrinsically weak and not likely caused by an intervening absorber. We found
rest-frame equivalent widths of EW(Ly+NV) Angstrom,
EW(CIV) Angstrom (3-sigma upper limit), and EW(MgII)
Angstrom. A small proximity zone size ( pMpc) indicates
a lifetime of only years from the last quasar
phase ignition. ALMA shows extended [CII] emission with a mild velocity
gradient. The inferred far-infrared luminosity
() is one of the highest
among all known quasar hosts at . Dust and [CII] emissions put a
constraint on the star formation rate of SFR
, similar to that of hyper-luminous
infrared galaxy. Considering the observed quasar lifetime and BLR formation
timescale, the weak-line profile in the quasar spectrum is most likely caused
by a BLR which is not yet fully formed rather than continuum boosting by
gravitational lensing or a soft continuum due to super-Eddington accretion.Comment: 28 pages, 16 figures, 3 tables, accepted for publication in Ap
Fc receptor-like 5 and anti-CD20 treatment response in granulomatosis with polyangiitis and microscopic polyangiitis
BACKGROUND. Baseline expression of FCRL5, a marker of naive and memory B cells, was shown to predict response to rituximab (RTX) in rheumatoid arthritis. This study investigated baseline expression of FCRL5 as a potential biomarker of clinical response to RTX in granulomatosis with polyangiitis (CPA) and microscopic polyangiitis (MPA). METHODS. A previously validated quantitative PCR-based (qPCR-based) platform was used to assess FCRL5 expression in patients with GPA/MPA (RAVE trial, NCT00104299). RESULTS. Baseline FCRL5 expression was significantly higher in patients achieving complete remission (CR) at 6,12, and 18 months, independent of other clinical and serological variables, among those randomized to RTX but not cyclophosphamide-azathioprine (CYC/AZA). Patients with baseline FCRL5 expression >= 0.01 expression units (termed FCRL5(hi)) exhibited significantly higher CR rates at 6,12, and 18 months as compared with FCRL5(lo) subjects (84% versus 57% [P = 0.016], 68% versus 40% [P = 0.02], and 68% versus 29% [P = 0.0009], respectively). CONCLUSION. Our data taken together suggest that FCRL5 is a biomarker of B cell lineage associated with increased achievement and maintenance of complete remission among patients treated with RTX and warrant further investigation in a prospective manner
The role of biophysical cohesion on subaqueous bed form size
Biologically active, fine-grained sediment forms abundant sedimentary deposits on Earth's surface, and mixed mud-sand dominates many coasts, deltas, and estuaries. Our predictions of sediment transport and bed roughness in these environments presently rely on empirically based bed form predictors that are based exclusively on biologically inactive cohesionless silt, sand, and gravel. This approach underpins many paleoenvironmental reconstructions of sedimentary successions, which rely on analysis of cross-stratification and bounding surfaces produced by migrating bed forms. Here we present controlled laboratory experiments that identify and quantify the influence of physical and biological cohesion on equilibrium bed form morphology. The results show the profound influence of biological cohesion on bed form size and identify how cohesive bonding mechanisms in different sediment mixtures govern the relationships. The findings highlight that existing bed form predictors require reformulation for combined biophysical cohesive effects in order to improve morphodynamic model predictions and to enhance the interpretations of these environments in the geological record
Circulating adrenomedullin estimates survival and reversibility of organ failure in sepsis: the prospective observational multinational Adrenomedullin and Outcome in Sepsis and Septic Shock-1 (AdrenOSS-1) study
Background: Adrenomedullin (ADM) regulates vascular tone and endothelial permeability during sepsis. Levels of circulating biologically active ADM (bio-ADM) show an inverse relationship with blood pressure and a direct relationship with vasopressor requirement. In the present prospective observational multinational Adrenomedullin and Outcome in Sepsis and Septic Shock 1 (, AdrenOSS-1) study, we assessed relationships between circulating bio-ADM during the initial intensive care unit (ICU) stay and short-term outcome in order to eventually design a biomarker-guided randomized controlled trial. Methods: AdrenOSS-1 was a prospective observational multinational study. The primary outcome was 28-day mortality. Secondary outcomes included organ failure as defined by Sequential Organ Failure Assessment (SOFA) score, organ support with focus on vasopressor/inotropic use, and need for renal replacement therapy. AdrenOSS-1 included 583 patients admitted to the ICU with sepsis or septic shock. Results: Circulating bio-ADM levels were measured upon admission and at day 2. Median bio-ADM concentration upon admission was 80.5 pg/ml [IQR 41.5-148.1 pg/ml]. Initial SOFA score was 7 [IQR 5-10], and 28-day mortality was 22%. We found marked associations between bio-ADM upon admission and 28-day mortality (unadjusted standardized HR 2.3 [CI 1.9-2.9]; adjusted HR 1.6 [CI 1.1-2.5]) and between bio-ADM levels and SOFA score (p < 0.0001). Need of vasopressor/inotrope, renal replacement therapy, and positive fluid balance were more prevalent in patients with a bio-ADM > 70 pg/ml upon admission than in those with bio-ADM †70 pg/ml. In patients with bio-ADM > 70 pg/ml upon admission, decrease in bio-ADM below 70 pg/ml at day 2 was associated with recovery of organ function at day 7 and better 28-day outcome (9.5% mortality). By contrast, persistently elevated bio-ADM at day 2 was associated with prolonged organ dysfunction and high 28-day mortality (38.1% mortality, HR 4.9, 95% CI 2.5-9.8). Conclusions: AdrenOSS-1 shows that early levels and rapid changes in bio-ADM estimate short-term outcome in sepsis and septic shock. These data are the backbone of the design of the biomarker-guided AdrenOSS-2 trial. Trial registration: ClinicalTrials.gov, NCT02393781. Registered on March 19, 2015
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