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International Ocean Discovery Program Expedition 401 recovered 983 m of sediment from Portugal’s southwest margin in the northeast Atlantic Ocean at Site U1609 (37°22.6259′ N, 9°35.9120′ W; 1659.5 m water depth). This site was designed to recover the distal contourites deposited by the Mediterranean Overflow Water contour current from the late Miocene to the Pleistocene. We report semiquantitative elemental results from X-ray fluorescence scanning of sediment cores from Site U1609 (Holes U1609A and U1609B) scanned at a 4–5 cm resolution from ~202 to 509 m core depth below seafloor, Method A, equivalent to ~4.52 to ~7.8 Ma. Raw element intensities (in counts per second) for Al, Si, Ca, Ti, Mn, Fe, Rb, Sr, Zr, and Ba are presented here and correlated with lithofacies variations. We also identify biogenic-terrestrial input proportions and illustrate downcore cyclicity and correlation patterns between terrigenous components (Al, Si, Ti, Mn, and Ba), as well as their anticorrelations with biogenic (Ca and Sr) inputs. The cyclical variations in elemental ratios may help stratigraphic correlation between Holes U1609A and U1609B, astronomical tuning of the spliced record, and sedimentary interpretations of changes to the Mediterranean–Atlantic gateway and the bottom current circulation along the Atlantic margin of Portugal before, during, and after the Messinian Salinity Crisis. 

This report presents the results of X-ray fluorescence (XRF) scanning of sediment cores from International Ocean Discovery Program (IODP) Expedition 401 Site U1385, conducted as part of the Investigating Miocene Mediterranean–Atlantic Gateway Exchange (IMMAGE) Land-2-Sea drilling project. The expedition investigated Atlantic–Mediterranean exchange during the Late Miocene, focusing on the Messinian Salinity Crisis and its impact on climate and oceanography. Site U1385 is located on the Promontório dos Principes de Avis, a promontory extending west from the Portuguese margin in the northeast Atlantic, and recovered sediments from the lowermost Pliocene to the Tortonian. XRF scanning provides semiquantitative elemental data at a 2 cm resolution, revealing cyclic patterns in elemental abundances that reflect lithologies and can be correlated cyclostratigraphically with orbital cycles. These data highlight strong positive correlations among terrigenous elements (Al, Si, Ti, Mn, and Ba) and negative correlations between terrigenous and biogenic (Ca and Sr) elements. These results contribute to understanding the paleoceanographic and paleoenvironmental conditions at Site U1385 during the Upper Miocene and Lower Pliocene, providing insights into sediment provenance, diagenetic processes, and climatic variations. 

Ultra-miniaturized microendoscopes are vital for numerous biomedical applications. Such minimally invasive imagers allow for navigation into hard-to-reach regions and observation of deep brain activity in freely moving animals. Conventional solutions use distal microlenses. However, as lenses become smaller and less invasive, they develop greater aberrations and restricted fields of view. In addition, most of the imagers capable of variable focusing require mechanical actuation of the lens, increasing the distal complexity and weight. Here, we demonstrate a distal lens-free approach to microendoscopy enabled by computational image recovery. Our approach is entirely actuation free and uses a single pseudorandom spatial mask at the distal end of a multicore fiber. Experimentally, this lensless approach increases the space-bandwidth product, i.e., field of view divided by resolution, by threefold over a best-case lens- based system. In addition, the microendoscope demonstrates color resolved imaging and refocusing to 11 distinct depth planes from a single camera frame without any actuated parts.