Nanomaterials with efficient carrier multiplication (CM), that is, generation of multiple electron-hole pairs by single photons, have been the object of intense scientific interest as potential enablers of high efficiency generation-III photovoltaics. In this work, we explore nanocrystal shape control as a means for enhancing CM. Specifically, we investigate the influence of aspect ratio (ρ) of PbSe nanorods (NRs) on both CM and the inverse of this process, Auger recombination. We observe that Auger lifetimes in NRs increase with increasing particle volume and for a fixed cross-sectional size follow a linear dependence on the NR length. For a given band gap energy, the CM efficiency in NRs shows a significant dependence on aspect ratio and exhibits a maximum at ρ ∼ 6-7 for which the multiexciton yields are a factor of ca. 2 higher than those in quantum dots with a similar bandgap energy. To rationalize our experimental observations, we analyze the influence of dimensionality on both CM and non-CM energy-loss mechanisms and offer possible explanations for the seemingly divergent effects the transition from zero- to one-dimensional confinement has on the closely related processes of Auger recombination and CM.
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Neurology
February 2025
Department of Neurology, Department of Stroke, University Hospital Cleveland Medical Center, Case Western Reserve University, Cleveland, OH.
Background And Objectives: Although previous trials have established the efficacy and safety of endovascular thrombectomy (EVT) in large ischemic core strokes, most of them excluded patients with extracranial internal carotid artery (e-ICA) occlusion. We aimed to compare outcomes in patients with e-ICA occlusion and large ischemic core infarcts treated with EVT vs medical management (MM).
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Matern Child Health J
January 2025
Department of Epidemiology and Biostatistics, Michigan State University, Fee Hall West Wing; 909 Wilson Rd, East Lansing, MI, 48824, USA.
Background: Dental care before pregnancy is critical for preventing poor oral health, which is associated with adverse pregnancy outcomes. People with low incomes, however, may face insurance-related barriers to obtaining dental care. Medicaid expansion under the Affordable Care Act increased access to dental care utilization among adults with low incomes.
View Article and Find Full Text PDFbioRxiv
January 2025
Department of Chemistry, 409 McCormick Road, University of Virginia, Charlottesville, VA 22904.
Antibody production is central to protection against new pathogens and cancers, as well as to certain forms of autoimmunity. Antibodies often originate in the lymph node (LN), specifically at the extrafollicular border of B cell follicles, where T and B lymphocytes physically interact to drive B cell maturation into antibody-secreting plasmablasts. In vitro models of this process are sorely needed to predict aspects of the human immune response.
View Article and Find Full Text PDFiScience
January 2025
Laboratory of Functional Molecules and Materials, School of Physics and Optoelectronic Engineering, Shandong University of Technology, 266 Xincun Xi road, Zibo 255000, P.R. China.
In recent years, photocatalytic materials with a nanofiber-like morphology have garnered a surge of academic attention due to their distinctive properties, including an expansive specific surface area, a considerable high aspect ratio, a pronounced resistance to agglomeration, superior electron survivability, and robust surface activity. Consequently, the synthesis of photocatalytic nanofiber materials through various methodologies has drawn considerable attention. The electrospinning technique has been established as a prevalent method for fabricating nanofiber-structured materials, owing to its advantageous properties, including the ability for mass production and the assurance of high continuity.
View Article and Find Full Text PDFTau exhibits change in both spatial extent and density of pathology along the Alzheimer's disease (AD) spectrum with each aspect contributing to the overall burden of pathological tau. Nevertheless, studies using Tau PET have measured either magnitude using standardized uptake value ratios (SUVRs) or extent using number of Tau+ regions. We hypothesized that combining these two dimensions into a single measure of Magnitude and eXtent, Tau-MaX, would provide improved quantification of global tau burden as well as allowing for a region-agnostic measure of global tau burden that does not require a pre-specified region of interest (ROI) or meta-ROI.
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