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The tip of the red giant branch (TRGB) provides a luminous standard candle for constructing distance ladders to measure the Hubble constant. In practice, its measurements via edge-detection response (EDR) are complicated by the apparent fuzziness of the tip and the multipeak landscape of the EDR. Previously, we optimized an unsupervised algorithm, Comparative Analysis of TRGBs, to minimize the variance among multiple halo fields per host without relying on individualized choices, achieving state-of-the-art ∼<0.05 mag distance measures for optimal data. Here we apply this algorithm to an expanded sample of SN Ia hosts to standardize these to multiple fields in the geometric anchor, NGC 4258. In concert with the Pantheon+ SN Ia sample, this analysis produces a (baseline) result of H 0 = 73.22 ± 2.06 km s−1 Mpc−1. The largest difference in H 0 between this and similar studies employing the TRGB derives from corrections for SN survey differences and local flows used in the most recent SN Ia compilations that were absent in earlier studies. The SN-related differences total ∼2.0 km s−1 Mpc−1. A smaller share, ∼1.4 km s−1 Mpc−1, results from the inhomogeneity of the TRGB calibration across the distance ladder. We employ a grid of 108 variants around the optimal TRGB algorithm and find that the median of the variants is 72.94 ± 1.98 km s−1 Mpc−1 with an additional uncertainty due to algorithm choices of 0.83 km s−1 Mpc−1. None of these TRGB variants result in an H 0 of less than 71.6 km s−1 Mpc−1.

A bright (m F150W,AB = 24 mag), z = 1.95 supernova (SN) candidate was discovered in JWST/NIRCam imaging acquired on 2023 November 17. The SN is quintuply imaged as a result of strong gravitational lensing by a foreground galaxy cluster, detected in three locations, and remarkably is the second lensed SN found in the same host galaxy. The previous lensed SN was called “Requiem,” and therefore the new SN is named “Encore.” This makes the MACS J0138.0−2155 cluster the first known system to produce more than one multiply imaged SN. Moreover, both SN Requiem and SN Encore are Type Ia SNe (SNe Ia), making this the most distant case of a galaxy hosting two SNe Ia. Using parametric host fitting, we determine the probability of detecting two SNe Ia in this host galaxy over a ∼10 yr window to be ≈3%. These observations have the potential to yield a Hubble constant (H 0) measurement with ∼10% precision, only the third lensed SN capable of such a result, using the three visible images of the SN. Both SN Requiem and SN Encore have a fourth image that is expected to appear within a few years of ∼2030, providing an unprecedented baseline for time-delay cosmography.

Hair cell bundles consist of stereocilia arranged in rows of increasing heights, connected by tip links that transmit sound-induced forces to shorter stereocilia tips. Auditory mechanotransduction channel complexes, composed of proteins TMC1/2, TMIE, CIB2, and LHFPL5, are located at the tips of shorter stereocilia. While most components can interact with the tip link in vitro, their ability to maintain the channel complexes at the tip link in vivo is uncertain. Using mouse models, we show that an additional component, LOXHD1, is essential for keeping TMC1-pore forming subunits at the tip link but is dispensable for TMC2. Using SUB-immunogold-SEM, we showed that TMC1 localizes near the tip link but mislocalizes without LOXHD1. LOXHD1 selectively interacts with TMC1, CIB2, LHFPL5, and tip-link protein PCDH15. Our results demonstrate that TMC1-driven mature auditory channels require LOXHD1 to stay connected to the tip link and remain functional, while TMC2-driven developmental channels do not. The Grillet lab identified an additional component of the auditory mechanotransduction Machinery, the protein LOXHD1, which is indispensable to keep the ion channel subunit TMC1 next to the tip-link, where the force induced-by sound is transmitted.

An attempt has been made to design lightweight polypyrrole/carbon fibers and polypyrrole/carbon fibers/ferrofluid (Fe 3 O 4 particles) composite sheets using novolac resin via compression molding for electromagnetic shielding applications. The optimized formulation has been achieved to get an excellent combination of thermal, mechanical, and electrical properties of the composite sheet. Structural and morphological studies were carried out by x-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy. Polypyrrole/carbon fibers composite sheets shows maximum flexural strength and a flexural modulus of 62.4 ± 1 MPa and 0.60 ± 0.02 GPa, respectively, with total shielding effectiveness of 22.8 dB in the Ku-band (12.4–18 GHz) but when ferrofluid is added to the polypyrrole/carbon fibers composite system, flexural strength increases to 92.3 ± 1 MPa and the same trend has been observed for flexural modulus with a value of 0.65 ± 0.04 GPa. This multiphase lightweight polypyrrole composite sheet having 34 vol.% of carbon fibers and 4 vol.% of Fe 3 O 4 nanoparticles offers total shielding effectiveness of 31.9 dB (>99.99% attenuation) in the Ku-band (12.4–18 GHz) frequency range with a thickness of ∼1.25 mm. This is accredited to high dielectric losses and magnetic losses in conducting composite sheets. The observed results suggest that lightweight compression molded polypyrrole composite sheets could be a potential commercial alternative for electromagnetic shielding applications.

Electromagnetic interference (EMI) shielding effectiveness (SE) of multi-walled carbon nanotubes-polymethyl methacrylate (MWCNT-PMMA) composites prepared by two different techniques was measured. EMI SE up to 40 dB in the frequency range 8.2-12.4 GHz (X-band) was achieved by stacking seven layers of 0.3-mm thick MWCNT-PMMA composite films compared with 30 dB achieved by stacking two layers of 1.1-mm thick MWCNT-PMMA bulk composite. The characteristic EMI SE graphs of the composites and the mechanism of shielding have been discussed. SE in this frequency range is found to be dominated by absorption. The mechanical properties (tensile, flexural strength and modulus) of the composites were found to be comparable or better than the pure polymer. The studies therefore show that the composite can be used as structurally strong EMI shielding material.

Multiply imaged supernovae (SNe) provide a novel means of constraining the Hubble constant (H0). Such measurements require a combination of precise models of the lensing mass distribution and an accurate estimate of the relative time delays between arrival of the multiple images. Only two multiply imaged SNe, Refsdal and H0pe, have enabled measurements of H0 thus far. Here we detail the third such measurement for SN Encore, a z = 1.95 Type Ia SN discovered in JWST/NIRCam imaging. We measure the time delay, perform simulations of additional microlensing and millilensing systematics, and combine with the mass models of Suyu et al. in a double-blind analysis to obtain our H0 constraint. Our final time-delay measurement is Δt1b,1a=−39.8−3.3+3.9 days, which is combined with seven lens models weighted by the likelihood of the observed multiple image positions for a result of H0=66.9−8.1+11.2kms−1Mpc−1 . The uncertainty on this measurement could be improved significantly if template imaging is obtained. Remarkably, a sibling to SN Encore (SN “Requiem”) was discovered in the same host galaxy, making the MACS J0138.0–2155 cluster the first system known to produce more than one observed multiply imaged SN. SN Requiem has a fourth image that is expected to appear within a few years, providing an unprecedented decade-long baseline for time-delay cosmography and an opportunity for a high-precision joint estimate of H0.

Supernovae (SNe) that have been multiply imaged by gravitational lensing are rare and powerful probes for cosmology. Each detection is an opportunity to develop the critical tools and methodologies needed as the sample of lensed SNe increases by orders of magnitude with the upcoming Vera C. Rubin Observatory and Nancy Grace Roman Space Telescope. The latest such discovery is of the quadruply imaged Type Ia SN 2022qmx (aka, “SN Zwicky”) at z = 0.3544. SN Zwicky was discovered by the Zwicky Transient Facility in spatially unresolved data. Here we present follow-up Hubble Space Telescope observations of SN Zwicky, the first from the multicycle “LensWatch (www.lenswatch.org)” program. We measure photometry for each of the four images of SN Zwicky, which are resolved in three WFC3/UVIS filters (F475W, F625W, and F814W) but unresolved with WFC3/IR F160W, and present an analysis of the lensing system using a variety of independent lens modeling methods. We find consistency between lens-model-predicted time delays (≲1 day), and delays estimated with the single epoch of Hubble Space Telescope colors (≲3.5 days), including the uncertainty from chromatic microlensing (∼1–1.5 days). Our lens models converge to an Einstein radius of θE=(0.168−0.005+0.009)″ , the smallest yet seen in a lensed SN system. The “standard candle” nature of SN Zwicky provides magnification estimates independent of the lens modeling that are brighter than predicted by ∼1.7−0.6+0.8 mag and ∼0.9−0.6+0.8 mag for two of the four images, suggesting significant microlensing and/or additional substructure beyond the flexibility of our image-position mass models.

Background This is a unique case that describes the presentation, investigations, and disease trajectory of a fatal, clonal CD8-positive T-cell lymphoproliferative disorder in an otherwise healthy and immunocompetent patient with Epstein-Barr virus seronegative status. Central nervous system involving T-cell lymphoproliferative disorders are rare and typically encountered in the setting of immunocompromise. These disorders are often associated with aggressive cytomorphological features and characteristic magnetic resonance imaging patterns, which were not seen in this case. Case presentation Here we describe a case of a 65 year-old male presenting with neuropsychiatric symptoms, truncal ataxia, and falls who’s bone marrow, cerebrospinal fluid, and brain biopsy were consistent with a clonal CD8-positive T-cell lymphoproliferative disorder that did not meet existing World Health Organization criteria for classification as T-cell lymphoma. The patient was treated with intrathecal methotrexate resulting in transient improvement of his symptoms followed by disease progression and death related to aspiration. Conclusions This case highlights the importance of urgent and comprehensive work-up in patients with clinical features suggestive of lymphoma with central nervous system involvement, despite atypical imaging features and lack of cytomorphological features satisfying current World Health Organization classification criteria.

We present observations of three core-collapse supernovae (CCSNe) in elliptical hosts, detected by the Zwicky Transient Facility Bright Transient Survey (BTS). SN 2019ape is a SN Ic that exploded in the main body of a typical elliptical galaxy. Its properties are consistent with an explosion of a regular SN Ic progenitor. A secondary g-band light-curve peak could indicate interaction of the ejecta with circumstellar material (CSM). An Hα-emitting source at the explosion site suggests a residual local star formation origin. SN 2018fsh and SN 2020uik are SNe II which exploded in the outskirts of elliptical galaxies. SN 2020uik shows typical spectra for SNe II, while SN 2018fsh shows a boxy nebular Hα profile, a signature of CSM interaction. We combine these 3 SNe with 7 events from the literature and analyze their hosts as a sample. We present multi-wavelength photometry of the hosts, and compare this to archival photometry of all BTS hosts. Using the spectroscopically complete BTS, we conclude that 0.3%−0.1+0.3 of all CCSNe occur in elliptical galaxies. We derive star formation rates and stellar masses for the host galaxies and compare them to the properties of other SN hosts. We show that CCSNe in ellipticals have larger physical separations from their hosts compared to SNe Ia in elliptical galaxies, and discuss implications for star-forming activity in elliptical galaxies.