In this work, we present measurements of the E-mode (EE) polarization power spectrum and temperature-E-mode (TE) cross-power spectrum of the cosmic microwave background using data collected by ...SPT-3G, the latest instrument installed on the South Pole Telescope. This analysis uses observations of a 1500 deg2 region at 95, 150, and 220 GHz taken over a four-month period in 2018. We report binned values of the EE and TE power spectra over the angular multipole range 300≤ℓ<3000, using the multifrequency data to construct six semi-independent estimates of each power spectrum and their minimum-variance combination. These measurements improve upon the previous results of SPTpol across the multipole ranges 300 ≤ ℓ ≤ 1400 for EE and 300 ≤ ℓ ≤ 1700 for TE, resulting in constraints on cosmological parameters comparable to those from other current leading ground-based experiments. We find that the SPT-3G data set is well fit by a ΛCDM cosmological model with parameter constraints consistent with those from Planck and SPTpol data. From SPT-3G data alone, we find H0=68.8±1.5 km s-1 Mpc-1 and σ8=0.789±0.016, with a gravitational lensing amplitude consistent with the ΛCDM prediction (AL=0.98±0.12). We combine the SPT-3G and the Planck data sets and obtain joint constraints on the ΛCDM model. The volume of the 68% confidence region in six-dimensional ΛCDM parameter space is reduced by a factor of 1.5 compared to Planck-only constraints, with no significant shifts in central values. We note that the results presented here are obtained from data collected during just half of a typical observing season with only part of the focal plane operable, and that the active detector count has since nearly doubled for observations made with SPT-3G after 2018.
Acute kidney injury (AKI) is a common complication following cardiac surgery performed on cardiopulmonary bypass (CPB) and has important implications for prognosis. The aetiology of cardiac ...surgery‐associated AKI is complex, but renal hypoxia, particularly in the medulla, is thought to play at least some role. There is strong evidence from studies in experimental animals, clinical observations and computational models that medullary ischaemia and hypoxia occur during CPB. There are no validated methods to monitor or improve renal oxygenation during CPB, and thus possibly decrease the risk of AKI. Attempts to reduce the incidence of AKI by early transfusion to ameliorate intra‐operative anaemia, refinement of protocols for cooling and rewarming on bypass, optimization of pump flow and arterial pressure, or the use of pulsatile flow, have not been successful to date. This may in part reflect the complexity of renal oxygenation, which may limit the effectiveness of individual interventions. We propose a multi‐disciplinary pathway for translation comprising three components. Firstly, large‐animal models of CPB to continuously monitor both whole kidney and regional kidney perfusion and oxygenation. Secondly, computational models to obtain information that can be used to interpret the data and develop rational interventions. Thirdly, clinically feasible non‐invasive methods to continuously monitor renal oxygenation in the operating theatre and to identify patients at risk of AKI. In this review, we outline the recent progress on each of these fronts.
Here, we present a sample-variance-limited measurement of the temperature power spectrum (TT) of the cosmic microwave background using observations of a ~1500 deg2 field made by the SPT-3G in 2018. ...We report multifrequency power spectrum measurements at 95, 150, and 220 GHz covering the angular multipole range 750 ≤ ℓ < 3000. We combine this TT measurement with the published polarization power spectrum measurements from the 2018 observing season and update their associated covariance matrix to complete the SPT-3G 2018 TT/TE/EE dataset. This is the first analysis to present cosmological constraints from SPT TT, TE, and EE power spectrum measurements jointly. We blind the cosmological results and subject the dataset to a series of consistency tests at the power spectrum and parameter level. We find excellent agreement between frequencies and spectrum types and our results are robust to the modeling of astrophysical foregrounds. We report results for Λ CDM and a series of extensions, drawing on the following parameters: the amplitude of the gravitational lensing effect on primary power spectra AL, the effective number of neutrino species Neff, the primordial helium abundance YP, and the baryon clumping factor due to primordial magnetic fields b. We find that the SPT-3G 2018 TT/TE/EE data are well fit by Λ CDM with a probability to exceed of 15%. For Λ CDM, we constrain the expansion rate today to H0 = 68.3 ± 1.5 km s–1 Mpc–1 and the combined structure growth parameter to S8 = 0.797 ± 0.042. The SPT-based results are effectively independent of Planck, and the cosmological parameter constraints from either dataset are within <1σ of each other. The addition of temperature data to the SPT-3G TE/EE power spectra improves constraints by 8–27% for each of the Λ CDM cosmological parameters. When additionally fitting AL, Neff, or Neff + YP, the posteriors of these parameters tighten by 5–24%. In the case of primordial magnetic fields, complete TT/TE/EE power spectrum measurements are necessary to break the degeneracy between b and ns, the spectral index of primordial density perturbations. We report a 95% confidence upper limit from SPT-3G data of b<1.0. The cosmological constraints in this work are the tightest from SPT primary power spectrum measurements to date and the analysis forms a new framework for future SPT analyses.
Ultralight axionlike particles (ALPs) are compelling dark matter candidates because of their potential to resolve small-scale discrepancies between Λ CDM predictions and cosmological observations. ...Axion-photon coupling induces a polarization rotation in linearly polarized photons traveling through an ALP field; thus, as the local ALP dark matter field oscillates in time, distant static polarized sources will appear to oscillate with a frequency proportional to the ALP mass. We use observations of the cosmic microwave background from SPT-3G, the current receiver on the South Pole Telescope, to set upper limits on the value of the axion-photon coupling constant gφγ over the approximate mass range 10-22–10-19 eV , corresponding to oscillation periods from 12 hours to 100 days. For periods between 1 and 100 days ( 4.7×10-22 eV≤mφ≤4.7×10-20 eV ), where the limit is approximately constant, we set a median 95% C.L. upper limit on the amplitude of on-sky polarization rotation of 0.071 deg. Assuming that dark matter comprises a single ALP species with a local dark matter density of 0.3 GeV/cm3 , this corresponds to gφγ<1.18×10-12 GeV-1× ( mφ1.0 × 10 - 21 eV ) . These new limits represent an improvement over the previous strongest limits set using the same effect by a factor of ~3.8 .
To assess the safety, pharmacokinetics, and exploratory efficacy of SM04690, a novel Wnt pathway inhibitor, as a potential disease modifying treatment for knee osteoarthritis (OA).
Subjects with ...Kellgren-Lawrence grade 2–3 knee OA were randomized in successive dose-escalation cohorts to receive a knee intra-articular (IA) injection with 0.03, 0.07, or 0.23 mg SM04690, or placebo (PBO) (4:1 ratio). Safety, pharmacokinetics, efficacy (WOMAC Total/Function/Pain, Pain VAS, Physician Global Assessment MDGA, and OMERACT-OARSI Response), OA-related biomarker (P1NP, ß-CTX, and cartilage oligomeric matrix protein COMP), and radiographic/imaging data were collected at baseline and during 24-week follow-up.
61 subjects (SM04690 n = 50; PBO n = 11) enrolled. Two dose limiting toxicities (DLTs), increased pain following injection and paroxysmal tachycardia (also the single serious AE), were reported in the 0.07 mg cohort. A total of 72 AEs were reported; Sixteen (occurring in eight subjects) were considered related to study medication. There were three discontinuations; one due to an AE (0.03 mg cohort). Bone marrow edema (BME) remained constant for most subjects. No doses were excluded from further study due to DLT criteria. Plasma levels of SM04690 were below the limit of detection at all time points. At Week 24, improvements from baseline were seen in all cohorts for the exploratory measures WOMAC Total, WOMAC Function, WOMAC Pain, MDGA, Pain VAS, and OMERACT-OARSI response. Joint space width (JSW) improvement was observed in the 0.07 mg cohort (P = 0.02 vs PBO).
SM04690 appeared safe and well tolerated, with no evidence of systemic exposure. Exploratory efficacy analyses suggested positive trends for measurements of OA pain, function and disease-modifying osteoarthritis drug (DMOAD) properties.
NCT02095548.
Highlights • Staphylococcus aureus transmigration was detected throughout murine decomposition • S. aureus abundance peaked 5-7 days post decomposition • Naturally sterile organs showed undulating ...S.aureus positivity during decomposition • S. aureus was widely distributed in organs in non-surface sterilized mice • Post-mortem microbial transmigration may be useful in providing PMI estimates
The motion of individual cesium atoms trapped inside an optical resonator is revealed with the atom-cavity microscope (ACM). A single atom moving within the resonator generates large variations in ...the transmission of a weak probe laser, which are recorded in real time. An inversion algorithm then allows individual atom trajectories to be reconstructed from the record of cavity transmission and reveals single atoms bound in orbit by the mechanical forces associated with single photons. In these initial experiments, the ACM yields 2-micrometer spatial resolution in a 10-microsecond time interval. Over the duration of the observation, the sensitivity is near the standard quantum limit for sensing the motion of a cesium atom.
Abstract
Including millimeter-wave data in multiwavelength studies of the variability of active galactic nuclei (AGN) can provide insights into AGN physics that are not easily accessible at other ...wavelengths. We demonstrate in this work the potential of cosmic microwave background (CMB) telescopes to provide long-term, high-cadence millimeter-wave AGN monitoring over large fractions of sky. We report on a pilot study using data from the SPTpol instrument on the South Pole Telescope (SPT), which was designed to observe the CMB at arcminute and larger angular scales. Between 2013 and 2016, SPTpol was used primarily to observe a single 500 deg
2
field, covering the entire field several times per day with detectors sensitive to radiation in bands centered at 95 and 150 GHz. We use SPT 150 GHz observations to create AGN light curves, and we compare these millimeter-wave light curves to those at other wavelengths, in particular
γ
-ray and optical. In this Letter, we focus on a single source, PKS 2326-502, which has extensive, day-timescale monitoring data in gamma-ray, optical, and now millimeter-wave between 2013 and 2016. We find PKS 2326-502 to be in a flaring state in the first 2 yr of this monitoring, and we present a search for evidence of correlated variability between millimeter-wave, optical
R-
band, and
γ
-ray observations. This pilot study is paving the way for AGN monitoring with current and upcoming CMB experiments such as SPT-3G, Simons Observatory, and CMB-S4, including multiwavelength studies with facilities such as Vera C. Rubin Observatories Large Synoptic Survey Telescope.
During past periods of advance, Arctic glaciers and ice sheets overrode soil, sediments, and vegetation and buried significant stores of organic matter (OM); these glaciers are now shrinking rapidly ...due to climate warming. Little is known about the biogeochemical processing of the OM buried beneath glacier ice which makes the processes associated with deglaciation difficult to predict. Subglacial sediments exposed at receding glacier fronts may represent a legacy of past biogeochemical processes. Here, we analyzed sediments from retreating fronts of 19 Arctic glaciers for their mineralogical and elemental composition, contents of major nutrients, OM biomarkers (aliphatic lipids and lignin‐derived phenols), 14C age, and microbial community structure. We show the character of the sediments is mostly determined by local glaciation history and bedrock lithology. Most subglacial sediments offer high amounts of readily bioavailable phosphorus (i.e., loose, labile, and Fe/Al P fractions) but lack readily accessible carbon substrates. The subglacial OM originated mainly from overridden terrestrial vascular plants. The results of OM biomarker analysis and 14C dating suggest the OM substrates degrade in the subglacial environment and are reworked by the resident microbial communities. We argue the biogeochemical legacy of the perishing subglacial environments is an important determinant for the early processes of proglacial ecological succession.
Plain Language Summary
The rapid melting of Arctic glaciers leaves behind large areas of sediments that have been covered by glacier ice and isolated for long periods of time. These sediments form the base of the new proglacial ecosystem; however, little is known about the legacy of subglacial biogeochemical processes. We comprehensively analyzed sediments from 19 Arctic glaciers to gain insight into the origin and fate of the present organic matter, nutrient content, and microbial communities. We propose that the character of the sediments is determined by local glaciation histories and also affected by the bedrock composition. We found that organic material in the sediments originates mainly from higher plants, overridden during past (Holocene and/or Late Pleistocene) periods of glacier advance. It degrades beneath the ice and is used as a substrate by microorganisms living at the glacier beds. While readily accessible carbon compounds are likely depleted in the exposed sediments, the macronutrient phosphorus, vital for the development of the new proglacial ecosystem, is available in high concentrations. We argue that the biogeochemical characteristics of the disappearing environments of glacier and ice sheet beds is an important factor for the early development of the expanding proglacial areas in the Arctic.
Key Points
Retreating Arctic glaciers are exposing sediments that have been isolated under the ice for thousands to tens of thousands of years
Extracted biomarkers indicates an overridden vegetation origin and significant degradation of organic matter in the subglacial environment
The biogeochemical legacy of subglacial sediments defines the initial stages of ecological succession in proglacial areas
Here, we present a measurement of gravitational lensing over 1500deg2 of the Southern sky using SPT-3G temperature data at 95 GHz and 150 GHz taken in 2018. The lensing amplitude relative to a ...fiducial Planck 2018 Lambda cold dark matter ( Λ CDM ) cosmology is found to be 1.020±0.060 , excluding instrumental and astrophysical systematic uncertainties. We conduct extensive systematic and null tests to check the robustness of the lensing measurements, and report a minimum-variance combined lensing power spectrum over angular multipoles of 50<L<2000 , which we use to constrain cosmological models. When analyzed alone and jointly with primary cosmic microwave background (CMB) spectra within the Λ CDM model, our lensing amplitude measurements are consistent with measurements from SPT-SZ, SPTpol, ACT, and Planck. Incorporating loose priors on the baryon density and other parameters including uncertainties on a foreground bias template, we obtain a 1σ constraint on σ8 Ω m 0.25=0.595±0.026 using the SPT-3G 2018 lensing data alone, where σ8 is a common measure of the amplitude of structure today and Ω m is the matter density parameter. Combining SPT-3G 2018 lensing measurements with baryon acoustic oscillation (BAO) data, we derive parameter constraints of σ8=0.810±0.033 , S8≡σ8 ( Ω m /0.3 ) 0.5= 0.836±0.039 , and Hubble constant H0=68.8-1.6+1.3km s -1Mpc-1 . Our preferred S8 value is higher by 1.6 to 1.8σ compared to cosmic shear measurements from DES-Y3, HSC-Y3, and KiDS-1000 at lower redshift and smaller scales. We combine our lensing data with CMB anisotropy measurements from both SPT-3G and Planck to constrain extensions of Λ CDM . Using CMB anisotropy and lensing measurements from SPT-3G only, we provide independent constraints on the spatial curvature of Ω K=0.014-0.026+0.023 (95% C.L.) and the dark energy density of Ω Λ =0.722-0.026+0.031 (68% C.L.). When combining SPT-3G lensing data with SPT-3G CMB anisotropy and BAO data, we find an upper limit on the sum of the neutrino masses of Σmν<0.30eV (95% C.L.). Due to the diferent combination of angular scales and sky area, this lensing analysis provides an independent check on lensing measurements by ACT and Planck.
PDF
