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We update the publicly available weak lensing shear measurement algorithm pyRRG for the JWST , and apply it to UNCOVER DR1 imaging of galaxy cluster Abell 2744. At short wavelengths (⁠|${\lt}2.5\, \mu$| m), shear measurements are consistent between independent observations through different JWST bandpasses, and calibrated within 1.5 per cent of those from the Hubble Space Telescope. At longer wavelengths, shear is underestimated by ∼5 per cent, probably due to coarser pixellization. We model the spatially varying point spread function using WebbPSF , whose moments are within 0.05 of real stars near the centre of the mosaic, where there are sufficient stars to also generate an empirical model. We measure shear from up to 162 galaxies arcmin−2 to derive a map of dark plus baryonic mass with 12 arcsec (55 kpc) spatial resolution. All code, catalogues, and maps are available from https://github.com/davidharvey1986/pyRRG. [ABSTRACT FROM AUTHOR]

We investigate how strong gravitational lensing can test contemporary models of massive elliptical (ME) galaxy formation, by combining a traditional decomposition of their visible stellar distribution with a lensing analysis of their mass distribution. As a proof of concept, we study a sample of three ME lenses, observing that all are composed of two distinct baryonic structures, a 'red' central bulge surrounded by an extended envelope of stellar material. Whilst these two components look photometrically similar, their distinct lensing effects permit a clean decomposition of their mass structure. This allows us to infer two key pieces of information about each lens galaxy: (i) the stellar mass distribution (without invoking stellar populations models) and (ii) the inner dark matter halo mass. We argue that these two measurements are crucial to testing models of ME formation, as the stellar mass profile provides a diagnostic of baryonic accretion and feedback whilst the dark matter mass places each galaxy in the context of LCDM large-scale structure formation. We also detect large rotational offsets between the two stellar components and a lopsidedness in their outer mass distributions, which hold further information on the evolution of each ME. Finally, we discuss how this approach can be extended to galaxies of all Hubble types and what implication our results have for studies of strong gravitational lensing. [ABSTRACT FROM AUTHOR]

A case is reported of multiple metachronous carcinomas of the small and large intestine in a child. The latter were associated with multiple adenomatous polyps in the colon. A desmoid tumour and multiple keloids developed in the laparotomy scars. The relationship of this case to Gardner's syndrome and polyposis coli is discussed and the literature on intestinal carcinoma in childhood is briefly reviewed. [ABSTRACT FROM PUBLISHER]