AMOC Trends From 1850 to 2100 At Interannual To Multi-Decadal Time Scales Corroborated By Changes In Salinity Budget

The Atlantic Meridional Overturning Circulation (AMOC) is a key player in the global coupled ocean-atmosphere climate system. To characterise the potential of an AMOC slowdown, a past and future trend probability analysis is applied using 16 models from the Coupled Model Intercomparison Project Phase 5. We determine the probability of AMOC annual to multidecadal trends under the historical period and two future climate scenarios (`business-as-usual’ scenario - RCP8.5 and `stabilisation’ scenario - RCP4.5). We show that the probability of a AMOC decline in model data shifts outside its range of intrinsic variability (determined from the pre-industrial control runs) for sustained 5-year trend or longer. This suggests that interannual AMOC events are not significantly affected by future climate scenario, and so potentially neither by anthropogenic forcing. Furthermore, under the ‘business-as-usual’ scenario the probability of a 20-year decline remains high (87\%) until 2100, however in a ‘stabilisation’ scenario the trend probability recovers its pre-industrial values by 2100. A 20-year unique event is identified from 1995 to 2015, marked by simultaneous unique features in the AMOC and salinity transport that are not replicated over any other 20-year period within the 250 years studied. These features include the maximum probability and magnitude of an `intense’ AMOC decline, and a sustained 20-year decline in subpolar salinity transport caused by internal oceanic processes (as opposed to external atmospheric forcing). This work therefore highlights the potential use of direct salinity transport observations, and ensemble mean numerical models to represent and understand changes in past, present, and future AMOC.

Three-dimensional Hybrid Simulation Results of a Variable Magnetic Helicity Signature at Proton Kinetic Scales

Three-dimensional hybrid kinetic simulations are conducted with particle protons and warm fluid electrons. Alfvénic fluctuations initialized at large scales and with wavevectors that are highly oblique with respect to the background magnetic field evolve into a turbulent energy cascade that dissipates at proton kinetic scales. Accompanying the proton scales is a spectral magnetic helicity signature with a peak in magnitude. A series of simulation runs are made with different large-scale cross helicity and different initial fluctuation phases and wavevector configurations. From the simulations a so-called total magnetic helicity peak is evaluated by summing contributions at a wavenumber perpendicular to the background magnetic field. The total is then compared with the reduced magnetic helicity calculated along spacecraft-like trajectories through the simulation box. The reduced combines the helicity from different perpendicular wavenumbers and depends on the sampling direction. The total is then the better physical quantity to characterize the turbulence. On average the ratio of reduced to total is 0.45. The total magnetic helicity and the reduced magnetic helicity show intrinsic variability based on initial fluctuation conditions. This variability can contribute to the scatter found in the observed distribution of solar wind reduced magnetic helicity as a function of cross helicity.

Volumetric assessment and longitudinal changes of brain structures in formalinized Beagle brains

High field MRI represents an advanced technique both for diagnostic and research purposes on animal models such as the Beagle dog. The increasing interest in non-invasive neuroscience, aging, and neuropathological research led to a need of reference values (in terms of volumetric assessment) for the typical brain structures involved and, nowadays, several canine brain MRI atlases have been provided. Since no reports are available regarding the measurements reproducibility and few information are available about formalin fixation effect on brain structures when applied to MRI segmentation, we assessed the segmentation variability of selected structures as a function of the operator (two operators segmented the same data) and their intrinsic variability within a sample of 11 Beagle dogs (9 females and 2 males, 1.6 ± 0.2 years). Then, we analyzed for one further Beagle dog (2 years old) the longitudinal changes in the brain segmentations of these structures corresponding four conditions: in vivo, post mortem (after euthanasia), ex vivo (brain extracted and studied after 1 month in formalin and after 11 months); all the MRI images were collected with a 3 T MRI scanner. Our findings suggest that the segmentation procedure can be considered overall reproducible since only slight statistical differences were detected, apart from the ventricles.Furthermore, in the post mortem/ ex vivo comparison, the majority of the structures showed a higher contrast leading to more reproducible segmentations across operators and a net increase of volume of the studied structures; this could be justified by the intrinsic relaxation time changes observed as a consequence of formalin fixation, that led to an improvement of brain structures visualization and then segmentation.To conclude, MRI based segmentation seems to be a useful and accurate tool that allows longitudinal studies, especially when applied to formalin fixed brains.

TESS Data for Asteroseismology: Light-curve Systematics Correction

Data from the Transiting Exoplanet Survey Satellite (TESS) have produced of the order of one million light curves at cadences of 120 s and especially 1800 s for every ∼27 day observing sector during its two-year nominal mission. These data constitute a treasure trove for the study of stellar variability and exoplanets. However, to fully utilize the data in such studies a proper removal of systematic-noise sources must be performed before any analysis. The TESS Data for Asteroseismology group is tasked with providing analysis-ready data for the TESS Asteroseismic Science Consortium, which covers the full spectrum of stellar variability types, including stellar oscillations and pulsations, spanning a wide range of variability timescales and amplitudes. We present here the two current implementations for co-trending of raw photometric light curves from TESS, which cover different regimes of variability to serve the entire seismic community. We find performance in terms of commonly used noise statistics meets expectations and is applicable to a wide range of intrinsic variability types. Further, we find that the correction of light curves from a full sector of data can be completed well within a few days, meaning that when running in steady state our routines are able to process one sector before data from the next arrives. Our pipeline is open-source and all processed data will be made available on the websites of the TESS Asteroseismic Science Operations Center and the Mikulski Archive for Space Telescopes.

Long-term Variability of the Composite Galaxy SDSS J103911-000057: A True Type-2 AGN Candidate

In this manuscript, the composite galaxy SDSS J103911-000057 (=SDSS J1039) is reported as a true Type-2 AGN candidate without hidden BLRs. Only narrow emission lines, not broad, detected in SDSS J1039 can be confirmed both by the F-test technique and by the expected broad emission lines with an EW smaller than 13.5 Å with a 99% confidence level. Meanwhile, a reliable AGN power-law component is preferred with a confidence level higher than 7σ in SDSS J1039. Furthermore, the long-term variability of SDSS J1039 from Catalina Sky Survey can be described by the DRW process with an intrinsic variability timescale τ ∼ 100 days, similar to normal quasars. And, based on BH mass in SDSS J1039 through the M BH–σ relation and on the correlation between AGN continuum luminosity and total Hα luminosity, the expected broad Hα, if there was one, could be reconstructed with a line width of about 300–1000 km s−1 and with a line flux of about 666 × 10−17 erg s−1 cm−2 under the virialization assumption to BLRs, providing robust evidence to reject the probability that the intrinsic probable broad Hα was overwhelmed by noises of the SDSS spectrum in SDSS J1039. Moreover, SDSS J1039 follows the same correlation between continuum luminosity and [O iii] line luminosity as the one for normal broad-line AGN, indicating SDSS J1039 classified as a changing-look AGN in the dim state can be ruled out. Therefore, under the current knowledge, SDSS J1039 is a better candidate for a true Type-2 AGN.

Intrinsic and Wind-Driven Decadal Variability of the Kuroshio Extension in Altimeter Observations

In this work we use satellite altimeter observations to study the mechanism of decadal variability of the Kuroshio Extension (KE), with special attention on jet-eddy energy transfer, and on the relationship between the wind-driven sea surface height anomalies (SSHAs) and those directly driven by intrinsic oceanic processes including jet and eddies. It is shown that energy feedback between the jet and mesoscale eddies can maintain the decadal oscillation of the KE. The wind-driven SSHAs are broad-scale and very weak compared to the intrinsic variability. Physically they can potentially trigger delayed responses of the latter by modulating vorticity advection from upstream but the statistical significance is low. KE perturbations resulting from the intrinsic variability, on the other hand, could feedback onto the wind-driven SSHAs by inducing anomalous basin-scale wind stress. The KE jet is thus an integrated system involving the jet and the eddies, possibly feeding back to, and paced by, wind stress anomalies.

Fast Pyrolysis Biochar Flammability behavior for Handling and Storage

Biochar is a fairly new material in the research arena with limited information on safety aspects related to transportation, storage, disposal or field application methods. The objective of this research was to assess the flammability characteristics of fast pyrolysis biochars with test methods EPA 1030 and ASTM 4982. Results indicated that biochar is a non-flammable substance when tested with EPA 1030 ignitability of solids. However, when tested with ASTM D4982, a fast screening method, biochars showed potential risks of flammability. However, the addition of 20-50% moisture reduced any flammability concern. Fast pyrolysis biochar was more prone to be flammable than traditional charcoal and slow pyrolysis biochar tested in this study. Still, fast pyrolysis biochars presented lower flammability potential (ASTM 4982) in comparison to its precursor biomass. The flammability propagation measured with EPA 1030, had high correlations with oxygen content and surface area of the fast pyrolysis biochar. The combustion reaction of fast pyrolysis biochar is a flameless combustion process, with a slow burning rate, and most commonly exhibiting a hot ember smoldering propagation front. This paper illustrates the necessity of performing recurring tests due to biochar’s intrinsic variability stemming from the different modes of production and feedstock used.

Analysis of High-precision TESS Photometry of the Black Hole X-Ray Binary Cygnus X-1: Evidence of Intrinsic Variability of the Luminous Blue Supergiant Component

We report on Transiting Exoplanet Survey Satellite (TESS) high-precision photometry of the iconic non-eclipsing 5.60 days (O9.7Iab+black hole) binary Cygnus X-1. Previous ground-based photometry reveals low-amplitude (∼0.04 mag) ellipsoidal light-variations that arise from the tidal (and rotational) distortion of the O9.7Iab companion. Additional small light-variations have also been reported by many observers. Short-cadence TESS photometry was conducted over ∼27 days during 2019 July–August. The photometry shows the expected ∼5.60 days binary ellipsoidal variations, but in addition ∼0.01–0.03 mag complex quasi-periodic brightness variations. The observations were analyzed to investigate the underlying extra-binary variability. We also determined a new time of minimum light and calculated an updated period and light elements. The quasi-periodic, (non-binary) light-variations likely arise from the complex pulsations of the blue supergiant.

8 Multiparameter characterization of CAR T cells

BackgroundAdoptive cell transfer of chimeric antigen receptor (CAR) modified T cells has demonstrated great therapeutic success against certain hematological malignancies. However, a substantial number of patients experienced relapse at some point after treatment with the underlying mechanisms not fully understood. Emerging data suggest that the undesired clinical outcome is related to different aspects, which include: the tumor heterogeneity, the tumor microenvironment, as well as intrinsic characteristics of the CAR T cells. In this work, we aimed to understand the diversity of CAR T cells generated from different donors, using multiparameter in vitro characterization.MethodsLeukapheresis from healthy donors were collected to generate CAR T cells using the GMP-compliant CliniMACS Prodigy® platform, enabling an automated and closed engineering of CAR T cells in a highly reproducible manner. We performed an in-depth characterization of the resulting CAR T cells by exploring differences in the immunophenotype, cell fitness and effector function of the freshly prepared as compared to frozen CAR T cell samples. Specifically, we designed several flow cytometry panels for the extensive characterization of immunophenotypes of interest such as: proliferative capacity, differentiation, activation and exhaustion. Cell fitness status was determined by the rate at which cells undergo apoptosis following stress. Finally, effector function was determined by the ability of the activated CAR T cells to secrete proinflammatory cytokines including IFN-g, TNF-a and IL-2. The associations between these different parameters were analyzed using comprehensive statistical approaches.ResultsWith our established workflow, over 20 healthy-donor derived CAR T cells were generated and characterized. We have observed donor-dependent variations and responses for most of the explored parameters. In general, the freezing and thawing process negatively affected cell fitness and effector function of the CAR T cells and resulted in altered immunophenotypes. Additionally, correlations between certain immunophenotypes and cell fitness/effector function were identified.ConclusionsCollectively, we established a workflow for multiparameter characterization of CAR T cells and assessed the intrinsic variability of CAR T cells for both research and clinical application.