Publications by authors named "Gregory Schneider"

Infrared emission features are observed towards diverse astronomical objects in the interstellar medium (ISM). Generally, the consensus is that these IR features originate from polycyclic aromatic hydrocarbons (PAHs) and are hence named aromatic infrared bands (AIBs). More recently, it has been suggested that nitrogen substituted PAHs (PANHs) contribute to the AIBs as well and it has even been shown that nitrogen inclusion in PAHs can improve the match with the AIBs, specifically around the 6.

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In this study, we explore the dynamics of grain boundaries in nanocrystalline carbon monolayers, focusing on their variation with electron beam energy and electron dose rate in a spherical and chromatic aberration-corrected transmission electron microscope. We demonstrate that a clean surface, a high-dose rate, and a 60 keV electron beam are essential for precise local control over the dynamics of grain boundaries. The structure of these linear defects has been evaluated using neural network-generated polygon mapping.

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Article Synopsis
  • * Nitrogen dopants mainly affect the selectivity of ORR products by generating hydroperoxide, while VGs improve the reaction kinetics and water output.
  • * The study suggests that both VGs and nitrogen dopants, along with oxygen dopants, contribute to the overall ORR activity, challenging the notion that only nitrogen species are responsible for catalysis in carbon materials.
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Polycyclic aromatic nitrogen heterocycles (PANHs) are present in various astronomical environments where they are subjected to intense radiation. Their photodissociation pathways give crucial insights into the cycle of matter in the universe, yet so far only the dissociation characteristics of few PANHs have been investigated. Moreover, most experiments use single photon techniques that only reveal the initial dissociation step, and are thus unsuited to replicate astronomical environments and timescales.

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The pressing demand for sustainable energy storage solutions has spurred the burgeoning development of aqueous zinc batteries. However, kinetics-sluggish Zn as the dominant charge carriers in cathodes leads to suboptimal charge-storage capacity and durability of aqueous zinc batteries. Here, we discover that an ultrathin two-dimensional polyimine membrane, featured by dual ion-transport nanochannels and rich proton-conduction groups, facilitates rapid and selective proton passing.

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A fundamental understanding of proton transport through graphene nanopores, defects, and vacancies is essential for advancing two-dimensional proton exchange membranes (PEMs). This study employs ReaxFF molecular dynamics, metadynamics, and density functional theory to investigate the enhanced proton transport through a graphene nanopore. Covalently functionalizing the nanopore with a benzenesulfonic group yields consistent improvements in proton permeability, with a lower activation barrier (≈0.

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Background: Arthroscopic lysis of adhesions is a treatment option for patients with painful, stiff knees as a result of arthrofibrosis following knee arthroplasty, in whom prior manipulation under anesthesia (MUA) has failed. Typically, nonoperative treatment in these patients has also failed, including aggressive physiotherapy, stretching, dynamic splinting, and various pain-management measures or medications. Range of motion in these patients is often suboptimal, and any gains in flexibility will likely have hit a plateau over many months.

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Background And Objectives: With continued advances in treatment options, patients with endoprosthetic reconstruction are living longer and consequently relying upon their devices for a longer duration. Major causes of endoprosthesis failure include aseptic loosening and mechanical failure. In the setting of tumor resection, loss of bone stock and use of radiation therapy increase the risk for these complications.

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Subunit vaccines would benefit from a safe particle-based adjuvant. Elastin-like polypeptide (ELP)-based micelles are interesting candidate adjuvants due to their well-defined size and easy modification with protein-based cargo. Coiled coils can facilitate noncovalent modifications, while potentially enhancing antigen delivery through interaction with cell membranes.

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Study Design: Retrospective cohort study.

Purpose: To compare radiographic outcomes between unilateral and bilateral cage placement in transforaminal lumbar interbody fusions (TLIF) and to determine if the rate of fusion at the 1-year postoperative point was different in patients who received bilateral versus unilateral cages.

Overview Of Literature: There is no clear evidence to dictate whether bilateral or unilateral cages promote superior radiographic or surgical outcomes in TLIF.

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The Angstrom-scale space between graphene and its substrate provides an attractive playground for scientific exploration and can lead to breakthrough applications. Here, we report the energetics and kinetics of hydrogen electrosorption on a graphene-covered Pt(111) electrode using electrochemical experiments, in situ spectroscopy, and density functional theory calculations. The graphene overlayer influences the hydrogen adsorption on Pt(111) by shielding the ions from the interface and weakening the Pt-H bond energy.

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Background: People experiencing homelessness (PEH) are recognized as members of a vulnerable population with significant health and social disparities. Due to the COVID-19 pandemic, these populations are at risk for increased morbidity and mortality. The Herbert Wertheim College of Medicine (HWCOM) of Florida International University (FIU) in collaboration with the Miami-Dade County Homeless Trust presents this case series based on the results of the Telemedicine Homeless Monitoring Project, launched in April 2020.

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Photosubstitutionally active ruthenium complexes show high potential as prodrugs for the photoactivated chemotherapy (PACT) treatment of tumors. One of the problems in PACT is that the localization of the ruthenium compound is hard to trace. Here, a ruthenium PACT prodrug, [Ru(3)(biq)(STF-31)](PF ) (where 3 = 3-(([2,2':6',2″-ter- pyridin]-4'-yloxy)propyl-4-(pyren-1-yl)butanoate) and biq = 2,2'-biquinoline), has been prepared, in which a pyrene tracker is attached via an ester bond.

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There is growing concern about the toxicity of colloidal aluminum salts used as adjuvants in subcutaneous allergen immunotherapy (SCIT). Therefore, alternative adjuvants and delivery systems are being explored to replace alum in SCIT. We applied micellar elastin-like polypeptides (ELPs), a type of self-assembling protein, to replace alum as vaccine adjuvant in birch pollen SCIT.

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Molecularly thin, nanoporous thin films are of paramount importance in material sciences. Their use in a wide range of applications requires control over their chemical functionalities, which is difficult to achieve using current production methods. Here, the small polycyclic aromatic hydrocarbon decacyclene is used to form molecular thin films, without requiring covalent crosslinking of any kind.

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In chemical vapor deposition of graphene, crossing over the melting temperature of the bulk catalyst is an effective approach to heal the defects and thus improve the crystallinity of the lattice. Here, electromagnetic absorption (the capability of metals to absorb radiated thermal energy) yields a thin skin of liquid metal catalyst at submelting temperatures, allowing the growth of high quality graphene. In fact, a chromium film initially deposited on one side of a copper foil absorbs the thermal energy radiated from a heating stage several times more effectively than a plain copper foil.

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The presence of defects and chemical dopants in metal-free carbon materials plays an important role in the electrocatalysis of the oxygen reduction reaction (ORR). The precise control and design of defects and dopants in carbon electrodes will allow the fundamental understanding of activity-structure correlations for tailoring catalytic performance of carbon-based, most particularly graphene-based, electrode materials. Herein, we adopted monolayer graphene - a model carbon-based electrode - for systematical introduction of nitrogen and oxygen dopants, together with vacancy defects, and studied their roles in catalyzing ORR.

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This paper describes the development and validation of a new questionnaire designed to measure and investigate attitudes towards interprofessional education (IPE) among health professions students. After a thorough literature review and survey of prior instruments, we created an instrument built around a single construct domain: attitudes toward interprofessional collaborative learning. Through a rigorous design methodology rooted in behavior change theory and an iterative question development process, we launched the 11-item "Brief Attitudes Survey for Interprofessional Collaborative Learning" (BASIC-L).

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Owing to their excellent electrical properties and chemical stability, graphene field-effect transistors (Gr-FET) are extensively studied for biosensing applications. However, hinging on surface interactions of charged biomolecules, the sensitivity of Gr-FET is hampered by ionic screening under physiological conditions with high salt concentrations up to frequencies as high as MHz. Here, an electrolyte-gated Gr-FET in reflectometry mode at ultrahigh frequencies (UHF, around 2 GHz), where the ionic screening is fully cancelled and the dielectric sensitivity of the device allows the Gr-FET to directly function in high-salt solutions, is configured.

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Unlabelled: Augmenting its nutrition education, the Herbert Wertheim College of Medicine Endocrinology course initially used a case-based, take-home assignment on type II diabetes dietary guidelines, with literature search requirement and a module on relevant social determinants of health (SDOH). Course evaluations indicated this assignment did not adequately improve student perceptions of learning. For the subsequent cohort, we changed to a large-group active learning session, requiring one faculty facilitator, where student teams created problem lists including SDOH and reviewed research articles to support evidence-based nutrition recommendations.

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In response to the COVID-19 pandemic, the Herbert Wertheim College of Medicine's Neighborhood Health Education Learning Program (NeighborhoodHELP) initiated a longitudinal assessment and mitigation of social and health care challenges for a population of approximately 850 underserved households. Here, we describe the needs assessment, ensuing interventions, and lessons learned during this pandemic.

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Estimates place low intake of fruits and vegetables, physical inactivity, and high BMI (overweight-obesity) as all in the top 12 causes of death. Food and dietary education are becoming a focus in how we approach disease prevention and management, and food prescription programs in particular are showing promise, especially in under-resourced, food-insecure communities. This paper describes a pilot food prescription program in a handful of uninsured patients enrolled in an interprofessional clinical and educational program of a medical school in South Florida.

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Interactions between water and graphene can be probed on a macroscopic level through wettability by measuring the water contact angle and on a microscopic level through water desorption kinetic studies using surface science methods. The contact angle studies of graphene pinpointed the critical role of sample preparation and measurement conditions in assessing the wettability of graphene. So far, studies of water desorption from graphene under the conditions of ultrahigh vacuum provided superior control over the environment but disregarded the importance of sample preparation.

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Molecular transistors, electromagnetic waveguides, plasmonic devices, and novel generations of nanofluidic channels comprise precisely separated gaps of nanometric and subnanometric spacing. Nonetheless, fabricating a nanogap/nanochannel is a technological challenge, currently tackled by several approaches such as breakdown electromigration and lithography. The aforementioned techniques, though, are limited, respectively, in terms of gap stability and ultimate resolution.

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