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1. MULTISENSOR DETECTION OF IMPROPER SIGNALS IN IMPROPER NOISE

   Tugnait, Jitendra K (March 2017, ICASSP proceedings)

   This paper addresses the problem of detecting the presence of a complex -valued, possibly improper, but unknown signal, common among two or more sensors (channels) in the presence of spatially independent, unknown, possibly improper and colored, noise. Past work on this problem is limited to signals observed in proper noise. A source of improper noise is IQ imbalance during down-conversion of bandpass noise to baseband. A binary hypothesis testing approach is formulated and a generalized likelihood ratio test (GLRT) is derived using the power spectral density estimator of an augmented sequence. An analytical solution for calculating the test threshold is provided. The results are illustrated via simulations. 

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2. Pneumatic Non-Equibiaxial Cell Stretching Device With Live-Cell Imaging

   https://doi.org/10.1109/TBME.2023.3319013  

   Wang, Jue; Chatterjee, Aritra; Zigan, Clarisse; Alborn, Maya; Chan, Deva D; Chortos, Alex (January 2023, IEEE Transactions on Biomedical Engineering)

   Objective: Adherent cell behavior is influ- enced by a complex interplay of factors, including chemical and mechanical signals. In vitro experiments that mimic the mechanical environment experienced by cells in vivo are crucial for understanding cellular behavior and the progression of disease. In this study, we developed and validated a low-cost pneumatically-controlled cell stretcher with independent control of strain in two directions of a membrane, enabling unequal biaxial stretching and real- time microscopy during actuation. Methods: The stretch- ing was achieved by two independent pneumatic channels controlled by electrical signals. We used finite element simulations to compute the membrane’s strain field and particle tracking algorithms based on image processing techniques to validate the strain fields and measure the cell orientation and morphology. Results: The device can supply uniaxial, equibiaxial, and unequal biaxial stretching up to 15% strain in each direction at a frequency of 1Hz, with a strain measurement error of less than 1%. Through live cell imaging, we determined that distinct stretching patterns elicited differing responses and alterations in cell orientation and morphology, particularly in terms of cell length and area. Conclusion: The device successfully pro- vides a large, uniform, and variable strain field for cell experiments, while also enabling real-time, live cell imag- ing. Significance: This scalable, low-cost platform provides mechanical stimulation to cell cultures by independently controlling strains in two directions. This could contribute to a deeper understanding of cellular response to bio- realistic strains and could be useful for future in vitro drug testing platforms. 

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3. Synthesis, structural analysis, and docking studies with SARS-CoV-2 of a trinuclear zinc complex with N -phenylanthranilic acid ligands

   https://doi.org/10.1107/S205322962200239X  

   Mbani O., Armel L.; Bonnand, Evan F.; Paboudam, Awawou G.; Brannon, Jacob P.; Gardner-Ricossa, Kevyn D.; Stieber, S. Chantal; Agwara, Moise O. (April 2022, Acta Crystallographica Section C Structural Chemistry)

   The structure of a trinuclear zinc complex, hexakis(μ 2 -2-anilinobenzoato)diaquatrizinc(II), [Zn 2 (C 13 H 10 NO 2 ) 6 (H 2 O) 2 ] or (NPA) 6 Zn 3 (H 2 O) 2 (NPA is 2-anilinobenzoate or N -phenylanthranilate), is reported. The complex crystallizes in the triclinic space group P -1 and the central Zn II atom is located on an inversion center. The NPA ligand is found to coordinate via the carboxylate O atoms with unique C—O bond lengths that support an unequal distribution of resonance over the carboxylate fragment. The axial H 2 O ligands form hydrogen bonds with neighboring molecules that stabilize the supramolecular system in rigid straight chains, with an angle of 180° along the c axis. π stacking is the primary stabilization along the a and b axes, resulting in a highly ordered supramolecular structure. Docking studies show that this unique supramolecular structure of a trinuclear zinc complex has potential for binding to the main protease (M pro ) in SARS-CoV-2 in a different location from Remdesivir, but with a similar binding strength. 

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4. Log Transformation Improves Dating of Phylogenies

   https://doi.org/10.1093/molbev/msaa222  

   Mai, Uyen; Mirarab, Siavash (September 2020, Molecular Biology and Evolution)

   Xia, Xuhua (Ed.)

   Abstract Phylogenetic trees inferred from sequence data often have branch lengths measured in the expected number of substitutions and therefore, do not have divergence times estimated. These trees give an incomplete view of evolutionary histories since many applications of phylogenies require time trees. Many methods have been developed to convert the inferred branch lengths from substitution unit to time unit using calibration points, but none is universally accepted as they are challenged in both scalability and accuracy under complex models. Here, we introduce a new method that formulates dating as a non-convex optimization problem where the variance of log-transformed rate multipliers are minimized across the tree. On simulated and real data, we show that our method, wLogDate, is often more accurate than alternatives and is more robust to various model assumptions. 

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5. A meta inspiral–merger–ringdown consistency test of general relativity with gravitational wave signals from compact binaries

   https://doi.org/10.1088/1361-6382/adf02a  

   Satish_Madekar, Sakshi; K_Johnson-McDaniel, Nathan; Gupta, Anuradha; Ghosh, Abhirup (August 2025, Classical and Quantum Gravity)

   Abstract The observation of gravitational waves from compact binary coalescences is a promising tool to test the validity of general relativity (GR) in a highly dynamical strong-field regime. There are now a variety of tests of GR performed on the observed compact binary signals. In this paper, we propose a new test of GR that compares the results of these individual tests. This meta inspiral–merger–ringdown consistency test (IMRCT) involves inferring the final mass and spin of the remnant black hole obtained from the analyses of two different tests of GR and checking for consistency. If there is a deviation from GR, we expect that different tests of GR will recover different values for the final mass and spin, in general. We check the performance of the meta IMRCT using a standard set of null tests used in various gravitational-wave analyses: the original IMRCT, the test infrastructure for GR, the flexible-theory-independent test, and the modified dispersion test. However, the meta IMRCT is applicable to any tests of GR that infer the initial masses and spins or the final mass and spin, including ones that are applied to binary neutron star or neutron star–black hole signals. We apply the meta IMRCT to simulated quasi-circular GR and non-GR binary black hole (BBH) signals as well as to eccentric BBH signals in GR (analysed with quasicircular waveforms). We find that the meta IMRCT gives consistency with GR for the quasi-circular GR signals and picks up a deviation from GR in the other cases, as do other tests. In some cases, the meta IMRCT finds a significant GR deviation for a given pair of tests (and specific testing parameters) while the individual tests do not, showing that it is more sensitive than the individual tests to certain types of deviations. In addition, we also apply this test to a few selected real compact binary signals and find them consistent with GR. 

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