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  1. Introduction: The plasma membrane protects a cell from the extracellular environment. As such it presents an obstacle that therapeutics needs to traverse in order to achieve efficacy. For example, small interfering RNAs (siRNAs) need to be delivered to the cytoplasm, where they can interact with the RNA interference machinery and initiate gene silencing. However, these macromolecules have poor membrane permeability, largely limiting their therapeutic potential. To address this challenge, current strategies involve encapsulating siRNAs into nanoparticles. However, upon cellular uptake, these nanoparticles are trapped in endosomes, which lack access to the cytoplasm. Towards developing an alternative strategy that provides directmore »access to the cytoplasm, we have been inspired by the unique capabilities of gap junctions to establish passageways between the cytoplasm of neighboring cells. Specifically, six connexins hexamerize to form a connexon hemichannel. Two hemichannels from neighboring cells dock to each other to form a complete gap junction channel, facilitating the exchange of molecular cargoes such as ions and siRNA. Therefore, incorporating the gap junction network into therapeutic delivery materials has the potential to enhance the delivery efficiency of siRNAs by directly depositing siRNAs into the cytoplasm.« less
  2. Recent GPS studies show that the Indo-Burma subduction system is locked with the implication of a potential large-magnitude earthquake. To inform better seismic hazard models in the region, we need an improved understanding of the crustal structure and the dynamics of the Indo-Burma subduction system. The Bangladesh-India-Myanmar (BIMA) tripartite project deployed 60 broadband seismometers across the subduction system and have been continuously recording data for ~2 years. In this study, we computed receiver functions from 30 high-quality earthquakes (M≥5.9) with epicentral distances between 30º and 90º recorded by the array. The algorithm utilized ensures the uniqueness of the seismic modelmore »and provides an uncertainty estimate of every converted wave amplitude. We stacked all the receiver functions produced at each station along the entire transect to generate a cross-sectional model of the average crustal structure. The level of detail in the image is improved by computing higher frequency receiver functions up to 4 Hz. The results represent some of the strongest constraints on crustal structure across the subduction system. Beneath the Neogene accretionary prism's outer belt, we observe a primary conversion associated with the Ganges Brahmaputra Delta that ranges in depth from ~10 km near the deformation front up to ~12 km at the eastern boundary. From the eastern end of the Neogene accretionary prism to the Sagaing Fault, we image the Indian subducting slab and the Central Myanmar basin. The depth-extent of seismicity associated with the Wadati-Benioff zone is consistent with the locations of primary conversions from the subducting plate. We further verify the converted phases of the slab by analyzing azimuthal moveout variations. The Central Myanmar basin is roughly bowl-shaped in cross-section with a maximum thickness of ~15 km about halfway between the Kabaw and Sagaing faults. The average crustal thickness beneath the Ganges-Brahmaputra delta is ~20 km, most likely representing a transitional crust formed from thinning of the continental crust intruded and underplated by igneous rocks. In contrast, the average thickness of the continental crust beneath the Central Myanmar basin is ~40 km. Our results provide a baseline model for future geophysical investigations of the Indo-Burma subduction zone.« less
  3. Abstract We report the results of the first joint observation of the KAGRA detector with GEO 600. KAGRA is a cryogenic and underground gravitational-wave detector consisting of a laser interferometer with 3 km arms, located in Kamioka, Gifu, Japan. GEO 600 is a British–German laser interferometer with 600 m arms, located near Hannover, Germany. GEO 600 and KAGRA performed a joint observing run from April 7 to 20, 2020. We present the results of the joint analysis of the GEO–KAGRA data for transient gravitational-wave signals, including the coalescence of neutron-star binaries and generic unmodeled transients. We also perform dedicated searches for binary coalescence signals and generic transientsmore »associated with gamma-ray burst events observed during the joint run. No gravitational-wave events were identified. We evaluate the minimum detectable amplitude for various types of transient signals and the spacetime volume for which the network is sensitive to binary neutron-star coalescences. We also place lower limits on the distances to the gamma-ray bursts analyzed based on the non-detection of an associated gravitational-wave signal for several signal models, including binary coalescences. These analyses demonstrate the feasibility and utility of KAGRA as a member of the global gravitational-wave detector network.« less
    Free, publicly-accessible full text available June 1, 2023
  4. Free, publicly-accessible full text available May 1, 2023