Calibration Methodology for the Scripps 13C/12C and 18O/16O stable Isotope program 1992-2018

This report details calibration method for measurements of 13C/12C and 18O/16O ratios of atmospheric CO2 by the Scripps CO2 program from 1992-2018.  The method depends principally on repeat analysis of CO2 derived from a suite of high-pressure gas cylinders filled with compressed natural air pumped at La Jolla.  The first set of three cylinders were given isotopic assignments in 1994 based on comparisons with material artifacts NBS16, NBS17, and NBS19.  Six cylinders subsequently brought into service were assigned values by comparing directly or indirectly with this first set.  A tenth cylinder with natural CO2 in air was obtained from MPI Jena.  Aliquots of CO2 from these cylinders, which serve as secondary standards, were extracted into heat-sealed glass ampoules (“flame-off tubes”) before introduction into the mass spectrometer.  Some of these ampoules have been stored for many years before analysis, allowing long-term isotopic drift of the cylinders to be quantified.  All secondary standards contain natural levels of N2O.  The method corrects for any detected drift, while also applying corrections for N2O interference, for isobaric interferences (“Craig correction”) and for an inter-lab offset identified in early comparisons with the isotope lab at the University of Groningen.  The Jena cylinder was found to be drifting upwards in δ18O at a rate of +0.10 ‰ per decade.  Five of the other nine cylinders were found to be drifting downwards in δ18O, δ13C, or both, at rates of up to -0.11‰ per decade.  The secondary standards were applied uniformly across a transition to a new mass spectrometer in 2000, thereby establishing continuity across this transition.  Results are presented also for instrumental precision based on replicate analyses of standards.  Drift-corrected analyses of the Jena cylinder establishes offsets of +0.037 ‰ in δ13C and +0.041 ‰ in δ18O between the Scripps and JRAS isotopic scales (Scripps more positive)

Riverine dissolved inorganic carbon export from the Southeast Alaskan Drainage Basin with implications for coastal ocean processes

Dissolved inorganic carbon (DIC) represents an important but poorly constrained form of lateral carbon flux to the oceans. With high precipitation rates, large glaciers, and dense temperate rainforest, Southeast Alaska plays a critical role in the transport of carbon to the Gulf of Alaska (GOA). Previous estimates of DIC flux across the Southeast Alaska Drainage Basin (SEAKDB) are poorly constrained in space and time. Our goal was to incorporate recent measurements of DIC concentrations with previous measurements from the U.S. Geological Survey in order to model the spatial and temporal patterns of riverine DIC transport from SEAK to the GOA. We aggregated DIC concentration measurements from 1957 to 2020 and associated measurements of mean daily discharge. We then constructed load estimation models to generate concentration predictions across 24 watersheds. By spatially matching measurements of DIC with SEAKDB watersheds, we extrapolated concentration predictions across 2,455 watersheds encompassing approximately 190,000 km2. Models were aggregated according to two factors, the presence of karst and the discharge regime. Finally, monthly flux predictions were generated for each watershed using predicted concentrations and runoff estimates from the Distributed Climate Water Balance Model. Mean annual DIC flux from the SEAKDB was 2.36 Tg C with an average yield of 12.52 g C m−2. Both karst presence and flow regimes modified DIC flux and speciation across coastal marine areas. The high resolution of DIC flux estimates will provide useful inputs for describing seasonal C dynamics, and further refines our understanding of C budgets in the Pacific temperate rainforest and the surrounding marine environment.National Science Foundation. Oak Ridge Institute for Science and Education.Abstract -- Plain Language Summary -- 1. Introduction -- 2. Methods -- 3. Results -- 4. Discussion -- 5. Conclusions -- Data Availability Statement -- Acknowledgements -- References.Ye

Tras los pasos de la Sílfide. Imaginarios españoles del ballet romántico a la danza moderna

La publicación que tiene la persona lectora entre sus manos realiza un recorrido de cien años de historia de la danza, un camino que toma como punto de partida la cultura visual del Romanticismo y que se ramifica fuera del ámbito geográfico de nuestro país, analizando los rasgos que definen y construyen la danza española y cómo estos se difundieron en los bailes en el extranjero.Las investigaciones contenidas en este libro son resultado del proyecto Tras los pasos de la Sílfide. Una historia de la danza en España, 1836-1936 (PGC2018-093710-A-I00)Peer reviewe

Post-intervention Status in Patients With Refractory Myasthenia Gravis Treated With Eculizumab During REGAIN and Its Open-Label Extension

OBJECTIVE: To evaluate whether eculizumab helps patients with anti-acetylcholine receptor-positive (AChR+) refractory generalized myasthenia gravis (gMG) achieve the Myasthenia Gravis Foundation of America (MGFA) post-intervention status of minimal manifestations (MM), we assessed patients' status throughout REGAIN (Safety and Efficacy of Eculizumab in AChR+ Refractory Generalized Myasthenia Gravis) and its open-label extension. METHODS: Patients who completed the REGAIN randomized controlled trial and continued into the open-label extension were included in this tertiary endpoint analysis. Patients were assessed for the MGFA post-intervention status of improved, unchanged, worse, MM, and pharmacologic remission at defined time points during REGAIN and through week 130 of the open-label study. RESULTS: A total of 117 patients completed REGAIN and continued into the open-label study (eculizumab/eculizumab: 56; placebo/eculizumab: 61). At week 26 of REGAIN, more eculizumab-treated patients than placebo-treated patients achieved a status of improved (60.7% vs 41.7%) or MM (25.0% vs 13.3%; common OR: 2.3; 95% CI: 1.1-4.5). After 130 weeks of eculizumab treatment, 88.0% of patients achieved improved status and 57.3% of patients achieved MM status. The safety profile of eculizumab was consistent with its known profile and no new safety signals were detected. CONCLUSION: Eculizumab led to rapid and sustained achievement of MM in patients with AChR+ refractory gMG. These findings support the use of eculizumab in this previously difficult-to-treat patient population. CLINICALTRIALSGOV IDENTIFIER: REGAIN, NCT01997229; REGAIN open-label extension, NCT02301624. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that, after 26 weeks of eculizumab treatment, 25.0% of adults with AChR+ refractory gMG achieved MM, compared with 13.3% who received placebo

Minimal Symptom Expression' in Patients With Acetylcholine Receptor Antibody-Positive Refractory Generalized Myasthenia Gravis Treated With Eculizumab

The efficacy and tolerability of eculizumab were assessed in REGAIN, a 26-week, phase 3, randomized, double-blind, placebo-controlled study in anti-acetylcholine receptor antibody-positive (AChR+) refractory generalized myasthenia gravis (gMG), and its open-label extension

Search for gravitational-lensing signatures in the full third observing run of the LIGO-Virgo network

Gravitational lensing by massive objects along the line of sight to the source causes distortions of gravitational wave-signals; such distortions may reveal information about fundamental physics, cosmology and astrophysics. In this work, we have extended the search for lensing signatures to all binary black hole events from the third observing run of the LIGO--Virgo network. We search for repeated signals from strong lensing by 1) performing targeted searches for subthreshold signals, 2) calculating the degree of overlap amongst the intrinsic parameters and sky location of pairs of signals, 3) comparing the similarities of the spectrograms amongst pairs of signals, and 4) performing dual-signal Bayesian analysis that takes into account selection effects and astrophysical knowledge. We also search for distortions to the gravitational waveform caused by 1) frequency-independent phase shifts in strongly lensed images, and 2) frequency-dependent modulation of the amplitude and phase due to point masses. None of these searches yields significant evidence for lensing. Finally, we use the non-detection of gravitational-wave lensing to constrain the lensing rate based on the latest merger-rate estimates and the fraction of dark matter composed of compact objects

Search for eccentric black hole coalescences during the third observing run of LIGO and Virgo

Despite the growing number of confident binary black hole coalescences observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that were already identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total mass M>70 M⊙) binaries covering eccentricities up to 0.3 at 15 Hz orbital frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place an upper limit for the merger rate density of high-mass binaries with eccentricities 0<e≤0.3 at 0.33 Gpc−3 yr−1 at 90\% confidence level

Ultralight vector dark matter search using data from the KAGRA O3GK run

Among the various candidates for dark matter (DM), ultralight vector DM can be probed by laser interferometric gravitational wave detectors through the measurement of oscillating length changes in the arm cavities. In this context, KAGRA has a unique feature due to differing compositions of its mirrors, enhancing the signal of vector DM in the length change in the auxiliary channels. Here we present the result of a search for U(1)B−L gauge boson DM using the KAGRA data from auxiliary length channels during the first joint observation run together with GEO600. By applying our search pipeline, which takes into account the stochastic nature of ultralight DM, upper bounds on the coupling strength between the U(1)B−L gauge boson and ordinary matter are obtained for a range of DM masses. While our constraints are less stringent than those derived from previous experiments, this study demonstrates the applicability of our method to the lower-mass vector DM search, which is made difficult in this measurement by the short observation time compared to the auto-correlation time scale of DM

Time-series of stable isotopes in dissolved inorganic carbon of surface seawater near Bermuda and Hawaii

The 13C/12C ratio of stable carbon isotopes in dissolved inorganic carbon (DIC) can provide insight into carbon cycle variability and trends in the surface ocean. Measurements of δ13C-DIC when combined with DIC can be used to estimate anthropogenic carbon uptake and marine productivity and can contribute to our understanding of the role that the ocean plays in the global carbon cycle. This dissertation describes surface ocean time-series measurements near Bermuda (S-BATS) and Hawaii (HOT) of δ13C-DIC, DIC, and alkalinity (ALK) as a part of the Scripps Seawater Program, focusing on δ13C-DIC. Prior to this study, there was a hiatus in seawater δ13C-DIC measurements at Scripps, while samples continued to be collected and archived for future analysis. This dissertation details the resumption of these measurements along with the calibration and methodology used for Scripps measurements of δ13C-DIC. We quantify the calibration contributions to uncertainty in the context of consistency between newer and older measurements. In addition, we introduce and document the stability of three new seawater secondary standards, including a method based on CO2 in compressed N2 gas. In these time-series records of nearly three decades, we show that the long-term trends and seasonal cycles in sDIC and δ13C-DIC at both S-BATS and HOT are consistent with earlier studies and independent time-series records. From the full record we find no long-term changes in the seasonal cycle of sDIC, δ13C-DIC, or computed pCO2. Consistent to some earlier studies we find significant correlations at S-BATS with the North Atlantic Oscillation and at HOT with the Pacific Decadal Oscillation (PDO). We also find correlations at HOT that were not previously noted including the PDO with sea surface temperature and mixed layer depth (MLD), as well as El Nino Southern Oscillation (NINO3.4) with sDIC and MLD. Lastly, we use a combination of observations and CESM hindcast simulations to explore upper ocean carbon variability in subtropical gyres. This allows us to examine the time-series in a broader geographic context, showing coherent patterns of variability across the North Atlantic and North Pacific subtropical gyres and illustrating key differences in the controls of variability at BATS and HOT