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Proxidant Injection Causes the Onset of Type 2 Diabetes in the Spontaneously Hypertensive Obese (SHROB/Kol) Rat
Get PDFThe Flora, Fauna, and Paleoenvironment of the Late Middle Miocene Quebrada Honda Basin, Bolivia (Eastern Cordillera, Central Andes)
Get PDFMiocene ecosystem change in the Central Andes is not well understood because of a dearth of well-dated fossil sites from the region. The late Middle Miocene (~13-12 Ma) Quebrada Honda Basin (QHB) in southern Bolivia (22° S) helps fill this gap and provide vital insights into Neotropical paleoenvironments. The site is among the best-characterized Middle Miocene terrestrial vertebrate sites of South America and has a robust temporal, spatial, and lithostratigraphic framework for analyzing its sedimentary facies, fossils, and paleoenvironment. Here, we present new plant silica (phytolith) assemblage data from the QHB as well as new analyses of QHB faunal data. Phytolith assemblage data indicate two broad vegetation types: one suggestive of more open habitats (≥ 60% presumably open-habitat grasses) and the other of more closed habitats (typically dominated by potential bamboos and other forest indicators). Compositional overlap suggests that these vegetation types represent distinct plant communities within a broader biome that lacks an exact modern analog among studied Neotropical vegetation; however, it was likely akin to modern Neotropical semi-deciduous/dry forest to wooded savanna. No clear temporal or spatial trends in phytolith composition are evident in the QHB, and the same is broadly true for QHB vertebrates based on analyses of 872 identified specimens. Abundances of some mammals (certain rodents, armadillos, turtles, and the notoungulate Hemihegetotherium) vary slightly among well-sampled local areas and stratigraphic intervals, paralleling phytolith assemblage data suggesting local heterogeneity. The new floral and faunal data, combined with previous studies of paleosols, ichnofossils, ectothermic vertebrates, and mammal ecological diversity of the QHB, point to a mosaic landscape in lowland subtropical to tropical conditions that did not change substantially during the preserved interval. These results add critically to our understanding of Neotropical landscape evolution, suggesting that the QHB had not undergone substantial uplift, counter to recent reconstructions of Andean orogeny in the Eastern Cordillera
Evaluation of Outcomes Between the Top-down Versus the Bottom-up Approach for Retropubic Midurethral Sling
Get PDFIntroduction and hypothesis: Retropubic midurethral sling (MUS) placement is the gold standard for the treatment of stress urinary incontinence in the USA. The procedure can be approached from either a top-down or a bottom-up direction, but there is a paucity of contemporary data regarding outcomes between these approaches. The aim of this study was to provide updated clinical outcomes data. Methods: This was a retrospective cohort study of women undergoing the retropubic MUS procedure alone or at the time of pelvic organ prolapse repair between 2010 and 2020 at a single academic medical center. The electronic medical record was used to extract demographic data, operative approach, and perioperative complications. The primary outcome was a composite incidence of any perioperative complication. Results: Of the 309 patients analyzed, 140 (45.3%) underwent top-down and 169 (54.7%) underwent bottom-up retropubic MUS placement. Patients undergoing top-down MUS placement were more likely to be older (mean age 58 vs 54, p=0.02), have a history of diabetes mellitus (20% vs 8.9%, p=0.004), and have had a prior hysterectomy (27% vs 16%, p=0.02). They were less likely to have a concurrent anterior (p\u3c0.001) or posterior repair (p\u3c0.001). Patients undergoing the top-down procedure were less likely to experience sling exposure (p=0.02); complications in the two groups were otherwise similar. Conclusions: The top-down approach to retropubic MUS placement was associated with lower rates of mesh erosion in this population of patients. Neither approach is associated with an increased overall risk of complications or de novo overactive bladder symptoms
All You Need is Unary: End-to-End Bit-Stream Processing in Hyperdimensional Computing
Get PDFHyperdimensional Computing (HDC) is a brain-inspired computing paradigm introduced to achieve energy efficiency with a lightweight and single-pass training model. Hypervectors (HVs) at the heart of the HDC systems play a fundamental role in elevating the accuracy and obtaining the desired performance. Image-based HV encoding requires two types of HVs: Position and Level HVs. State-of-the-art approaches utilize pseudo-random methods for generating these HVs, which might degrade system performance and cause higher power consumption due to poor randomness in HV generation. These conventional methods require iteratively calculating orthogonal Positional HVs for acceptable accuracy. This work proposes a fast, ultra-lightweight, and high-quality HV generator incorporating low-discrepancy random sequences and the emerging unary bit-stream processing. For the first time, we employ unary computing (UC) to generate Level HVs, demonstrating that there is no need for randomness in HDC systems. We generate Position HVs using a single-source quasi-random sequence with a recurrence property. Our proposed HV generation technique improves the overall HDC accuracy by up to 6.4% for the medical MNIST dataset while reducing the power consumption of HV generation by 98%
A Distinct Radial Acceleration Relation Across the Brightest Cluster Galaxies and Galaxy Clusters
Get PDFRecent studies reveal a radial acceleration relation (RAR) in galaxies, which illustrates a tight empirical correlation connecting the observational acceleration and the baryonic acceleration with a characteristic acceleration scale. However, a distinct RAR has been revealed on brightest cluster galaxy (BCG) cluster scales with a seventeen-times-larger acceleration scale due to the gravitational lensing effect. In this work, we systematically explore the acceleration and mass correlations between dynamical and baryonic components in 50 BCGs. To investigate the dynamical RAR in BCGs, we derived their dynamical accelerations from the stellar kinematics using the Jeans equation through Abel inversion and adopted the baryonic mass from Sloan Digital Sky Survey photometry. We explored the spatially resolved kinematic profiles with the largest integral field spectroscopy (IFS) data collected by the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey. Our results demonstrate that the dynamical RAR in BCGs is consistent with the lensing RAR on BCG-cluster scales as well as a larger acceleration scale. This finding may imply that BCGs and galaxy clusters have fundamental differences from field galaxies. We also find a mass correlation, but it is less tight than the acceleration correlation
CMS Silicon Pixel Detector Callibration
Get PDFThe Compact Muon Solenoid (CMS) pixel group at Cornell University is building a silicon pixel detector test station that will model the revolutionary detection and data acquisition system designed for the CMS experiment at the Large Hadron Collider (LHC) at CERN. When fully implemented at the LHC, the detector\u27s sixty-six million pixels will be able to track and time passing charged particles that result from proton-proton collisions happening every twenty-five nanoseconds. With parts of the Cornell test station apparatus already functional, we have begun to understand and optimize the detector\u27s programmable settings that tune its performance. The success of these optimizations has been quantified by performing various calibrations also being developed here, that will also be used at the LHC to ensure that the pixel detector is working properly and taking the most accurate data possible
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