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Japanese Rhinoceros beetles (Trypoxylus dichotomous), known primarily for their large horns, are a classic example of ornate weaponry produced through sexual selection. The male beetle’s prominent horns are used in male-to-male combat for dominance and access to females. Observations in the lab and the field suggest that multiple forms of signaling are also involved in both the aggressive interactions and female mate choice. One such signal seems to be the songs created through male abdominal stridulation. Males perform both an alarm-style chirp (also seen in aggressive interactions) and rhythmic “purring” prior to copulation attempts. Several questions arise in relation to this behavior and its effect on mating outcomes: Is there a relationship between song characteristics and morphological characteristics? Can vibrations be transmitted through the surrounding substrate? Is there a relationship between song characteristics and courtship outcomes? To analyze these songs in the field, a Polytech VibroGo VG-200 laser vibrometer was used to measure the velocity of both the male’s elytra and surrounding tree bark during courtship. Vibrational amplitude and periodicity, corresponding location, beetle characteristics, and courtship details were collected. Male courtship song characteristics will be compared to morphological variables, as well as courtship outcomes. Substrate vibration transmission and attenuation will also be discussed. 

Existing three-dimensional (3D) culture techniques are limited by trade-offs between throughput, capacity for high-resolution imaging in living state, and geometric control. Here, we introduce a modular microscale hanging drop culture where simple design elements allow high replicates for drug screening, direct on-chip real-time or high-resolution confocal microscopy, and geometric control in 3D. Thousands of spheroids can be formed on our microchip in a single step and without any selective pressure from specific matrices. Microchip cultures from human LN229 glioblastoma and patient-derived mouse xenograft cells retained genomic alterations of originating tumors based on mate pair sequencing. We measured response to drugs over time with real-time microscopy on-chip. Last, by engineering droplets to form predetermined geometric shapes, we were able to manipulate the geometry of cultured cell masses. These outcomes can enable broad applications in advancing personalized medicine for cancer and drug discovery, tissue engineering, and stem cell research. 

ABSTRACT Eclipsing binaries are important benchmark objects to test and calibrate stellar structure and evolution models. This is especially true for binaries with a fully convective M-dwarf component for which direct measurements of these stars’ masses and radii are difficult using other techniques. Within the potential of M-dwarfs to be exoplanet host stars, the accuracy of theoretical predictions of their radius and effective temperature as a function of their mass is an active topic of discussion. Not only the parameters of transiting exoplanets but also the success of future atmospheric characterization relies on accurate theoretical predictions. We present the analysis of five eclipsing binaries with low-mass stellar companions out of a subsample of 23, for which we obtained ultra-high-precision light curves using the CHEOPS satellite. The observation of their primary and secondary eclipses are combined with spectroscopic measurements to precisely model the primary parameters and derive the M-dwarfs mass, radius, surface gravity, and effective temperature estimates using the PYCHEOPS data analysis software. Combining these results to the same set of parameters derived from TESS light curves, we find very good agreement (better than 1 per cent for radius and better than 0.2 per cent for surface gravity). We also analyse the importance of precise orbits from radial velocity measurements and find them to be crucial to derive M-dwarf radii in a regime below 5 per cent accuracy. These results add five valuable data points to the mass–radius diagram of fully convective M-dwarfs.