The hypothesis that the late Universe is isotropic and homogeneous is adopted by most cosmological studies, including studies of galaxy clusters. The cosmic expansion rate
H
0
is thought to be ...spatially constant, while bulk flows are often presumed to be negligible compared to the Hubble expansion, even at local scales. The effects of bulk flows on the redshift–distance conversion are hence usually ignored. Any deviation from this consensus can strongly bias the results of such studies, and thus the importance of testing these assumptions cannot be understated. Scaling relations of galaxy clusters can be effectively used for this testing. In previous works, we observed strong anisotropies in cluster scaling relations, whose origins remain ambiguous. By measuring many different cluster properties, several scaling relations with different sensitivities can be built. Nearly independent tests of cosmic isotropy and large bulk flows are then feasible. In this work, we make use of up to 570 clusters with measured properties at X-ray, microwave, and infrared wavelengths to construct ten different cluster scaling relations and test the isotropy of the local Universe; to our knowedge, we present five of these scaling relations for the first time. Through rigorous and robust tests, we ensure that our analysis is not prone to generally known systematic biases and X-ray absorption issues. By combining all available information, we detect an apparent 9% spatial variation in the local
H
0
between (
l
,
b
)∼(280°
−35°
+35°
, −15°
−20°
+20°
) and the rest of the sky. The observed anisotropy has a nearly dipole form. Using isotropic Monte Carlo simulations, we assess the statistical significance of the anisotropy to be > 5
σ
. This result could also be attributed to a ∼900 km s
−1
bulk flow, which seems to extend out to at least ∼500 Mpc. These two effects will be indistinguishable until more high-
z
clusters are observed by future all-sky surveys such as eROSITA.
The extracellular, matrix-modifying enzyme lysyl oxidase (LOX) has recently been linked to colorectal cancer (CRC) progression, in particular to the stages of invasion and metastasis. In this report, ...we use cell lines expressing a catalytically inactive mutant form of LOX to show that catalytic activity is required for LOX-mediated effects on proliferation and invasion in both in vitro and in vivo models of CRC. Furthermore, we use rheology to measure the relative stiffness of modified collagen matrices and subcutaneous tumors, and show that LOX-induced collagen cross-linking results in stiffening of the matrix both in vitro and in vivo. We observe a strong association between matrix stiffness and activation of the FAK (focal adhesion kinase)/SRC-signaling pathway, with a stiffer environment resulting in increased FAK/SRC phosphorylation and a more proliferative and invasive phenotype. We are the first to show a direct relationship between LOX enzymatic activity and tissue stiffness, and to demonstrate a role for stiffness in driving CRC progression. Our findings provide significant evidence to suggest that therapeutic inhibition of LOX activity may provide a novel effective treatment option for patients with metastatic CRC.
ABSTRACT We present ALMA measurements of a merger shock using the thermal Sunyaev-Zel'dovich (SZ) effect signal, at the location of a radio relic in the famous El Gordo galaxy cluster at . ...Multi-wavelength analysis in combination with the archival Chandra data and a high-resolution radio image provides a consistent picture of the thermal and non-thermal signal variation across the shock front and helps to put robust constraints on the shock Mach number as well as the relic magnetic field. We employ a Bayesian analysis technique for modeling the SZ and X-ray data self-consistently, illustrating respective parameter degeneracies. Combined results indicate a shock with Mach number , which in turn suggests a high value of the magnetic field (of the order of 4-10 ) to account for the observed relic width at 2 GHz. At roughly half the current age of the universe, this is the highest-redshift direct detection of a cluster shock to date, and one of the first instances of an ALMA-SZ observation in a galaxy cluster. It shows the tremendous potential for future ALMA-SZ observations to detect merger shocks and other cluster substructures out to the highest redshifts.
Radio relics are Mpc-scale diffuse synchrotron sources found in galaxy cluster outskirts. They are believed to be associated with large-scale shocks propagating through the intracluster medium, ...although the connection between radio relics and the cluster merger shocks is not yet proven conclusively. We present a first tentative detection of a pressure jump in the well-known relic of the Coma cluster through Sunyaev-Zel'dovich effect (SZE) imaging. The SZE data are extracted from the first public all-sky data release of Planck and we use high-frequency radio data at 2.3 GHz to constrain the shock-front geometry. The SZE data provide evidence for a pressure discontinuity, consistent with the relic position, without requiring any additional prior on the shock-front location. The derived Mach number M=2.9 ... is consistent with X-ray and radio results. A high-pressure 'filament' without any pressure discontinuity is disfavoured by X-ray measurements and a 'sub-cluster' model based on the infalling group NGC 4839 can be ruled out considering the published mass estimates for this group. These results signify a first attempt towards directly measuring the pressure discontinuity for a radio relic and the first SZE-detected shock feature observed near the virial radius of a galaxy cluster. (ProQuest: ... denotes formulae/symbols omitted.)
Context.
The
Fred Young
Submillimeter Telescope (FYST) and the Simons Observatory Large Aperture Telescope (SO LAT) will deliver unprecedented high-resolution measurements of microwave sky emissions. ...Notably, one of those microwave sky emissions, the thermal Sunyaev–Zeldovich (tSZ) signal, is an essential probe for cluster astrophysics and cosmology. However, an obstacle to its measurement is contamination by the cosmic infrared background (CIB), especially at high frequencies.
Aims.
Our goal is to assess the detection and purity of tSZ power spectrum measurements from these two telescopes. We demonstrate that FYST’s high-frequency coverage helps lower CIB contamination and improves signal detection.
Methods.
We simulated the various components of the microwave sky at the frequencies, sensitivities, and beam sizes of the upcoming SO LAT and FYST telescopes using full-sky Hierarchical Equal Area isoLatitude Pixelisation (HEALPix) map templates from the Websky simulations and the Python Sky Model (PySM). We used a map-based internal linear combination (ILC) and a constrained ILC (CILC) to extract the tSZ signal and compute residual noises to assess CIB contamination and signal recovery.
Results.
We find that the CIB’s residual noise power spectrum in the ILC-recovered tSZ is lowered by ∼35% on average over the scales
ℓ
∈ 500, 5000 when SO LAT and FYST are combined compared to when SO LAT is used alone. We find that when using CILC to deproject CIB, the combined abilities of SO LAT and FYST offer a large
ℓ
∈ 1800, 3500 window in which the recovered tSZ power spectrum is not noise dominated.
Context. Inferences about dark matter, dark energy, and the missing baryons all depend on the accuracy of our model of large-scale structure evolution. In particular, with cosmological simulations in ...our model of the Universe, we trace the growth of structure, and visualize the build-up of bigger structures from smaller ones and of gaseous filaments connecting galaxy clusters. Aims. Here we aim to reveal the complexity of the large-scale structure assembly process in great detail and on scales from tens of kiloparsecs up to more than 10 Mpc with new sensitive large-scale observations from the latest generation of instruments. We also aim to compare our findings with expectations from our cosmological model. Methods. We used dedicated SRG/eROSITA performance verification (PV) X-ray, ASKAP/EMU Early Science radio, and DECam optical observations of a ~15 deg2 region around the nearby interacting galaxy cluster system A3391/95 to study the warm-hot gas in cluster outskirts and filaments, the surrounding large-scale structure and its formation process, the morphological complexity in the inner parts of the clusters, and the (re-)acceleration of plasma. We also used complementary Sunyaev-Zeldovich (SZ) effect data from the Planck survey and custom-made Galactic total (neutral plus molecular) hydrogen column density maps based on the HI4PI and IRAS surveys. We relate the observations to expectations from cosmological hydrodynamic simulations from the Magneticum suite. Results. We trace the irregular morphology of warm and hot gas of the main clusters from their centers out to well beyond their characteristic radii, r200. Between the two main cluster systems, we observe an emission bridge on large scale and with good spatial resolution. This bridge includes a known galaxy group but this can only partially explain the emission. Most gas in the bridge appears hot, but thanks to eROSITA’s unique soft response and large field of view, we discover some tantalizing hints for warm, truly primordial filamentary gas connecting the clusters. Several matter clumps physically surrounding the system are detected. For the “Northern Clump,” we provide evidence that it is falling towards A3391 from the X-ray hot gas morphology and radio lobe structure of its central AGN. Moreover, the shapes of these X-ray and radio structures appear to be formed by gas well beyond the virial radius, r100, of A3391, thereby providing an indirect way of probing the gas in this elusive environment. Many of the extended sources in the field detected by eROSITA are also known clusters or new clusters in the background, including a known SZ cluster at redshift z = 1. We find roughly an order of magnitude more cluster candidates than the SPT and ACT surveys together in the same area. We discover an emission filament north of the virial radius of A3391 connecting to the Northern Clump. Furthermore, the absorption-corrected eROSITA surface brightness map shows that this emission filament extends south of A3395 and beyond an extended X-ray-emitting object (the “Little Southern Clump”) towards another galaxy cluster, all at the same redshift. The total projected length of this continuous warm-hot emission filament is 15 Mpc, running almost 4 degrees across the entire eROSITA PV observation field. The Northern and Southern Filament are each detected at >4σ. The Planck SZ map additionally appears to support the presence of both new filaments. Furthermore, the DECam galaxy density map shows galaxy overdensities in the same regions. Overall, the new datasets provide impressive confirmation of the theoretically expected structure formation processes on the individual system level, including the surrounding warm-hot intergalactic medium distribution; the similarities of features found in a similar system in the Magneticum simulation are striking. Our spatially resolved findings show that baryons indeed reside in large-scale warm-hot gas filaments with a clumpy structure.
The study of low energy weak interactions of light quarks and leptons continues to provide important insights into both the Standard Model as well as the physics that may lie beyond it. We review the ...status and future prospects for low energy electroweak physics. Recent important experimental and theoretical developments are discussed and open theoretical issues are highlighted. Particular attention is paid to neutrino physics, searches for permanent electric dipole moments, neutral current tests of the running of the weak mixing angle, weak decays, and muon physics. We argue that the broad range of such studies provides an important complement to high energy collider searches for physics beyond the Standard Model. The use of low energy weak interactions to probe novel aspects of hadron structure is also discussed.
Purpose
The purpose of the present study was to establish a semi‐automated threshold‐based image segmentation algorithm to detect and objectively quantify corneal cystine crystal deposition in ocular ...cystinosis with anterior segment optical coherence tomography (AS‐OCT).
Methods
This prospective, observational, comparative study included 88 eyes of 45 patients from the German Cystinosis Registry Study as well as 68 eyes of 35 healthy control subjects. All eyes were imaged with AS‐OCT (Cirrus HD‐OCT 5000, Carl Zeiss Meditec AG, Jena, Germany). As an initial step, B‐scan images were subjectively analysed for typical changes in morphology in comparison to healthy controls. Based on the experience gained, an objective semi‐automated B‐scan image segmentation algorithm was developed using a grey scale value‐based threshold method to automatically quantify corneal crystals.
Results
On AS‐OCT B‐scans, corneal crystals appeared as hyperreflective deposits within the corneal stroma. The crystals were distributed either in all stromal layers (43 eyes, 49%) or confined to the anterior (23 eyes, 26%) or posterior stroma (22 eyes, 25%), respectively. The novel automatic B‐scan image segmentation algorithm was most efficient in delineating corneal crystals at higher grey scale thresholds (e.g. 226 of a maximum of 255). Significant differences in suprathreshold grey scale pixels were observable between cystinosis patients and healthy controls (p < 0.001). In addition, the algorithm was able to detect an age‐dependent depth distribution profile of crystal deposition.
Conclusion
Objective quantification of corneal cystine crystal deposition is feasible with AS‐OCT and can serve as a novel biomarker for ocular disease control and topical treatment monitoring.
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