Publications by authors named "DA Fischer"

Anaphylaxis is an acute, potentially fatal systemic hypersensitivity reaction with varied mechanisms and clinical presentations. Although prompt recognition and treatment of anaphylaxis are imperative, both patients and healthcare professionals often fail to recognize and diagnose its early signs. Clinical manifestations vary widely, however, the most common signs are cutaneous symptoms, including urticaria and angioedema.

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Fluoridating reagents are used to model interfacial reactions in fluoride-ion batteries. Topochemical F-ion insertion is seen for one-dimensional (1D) tunnel-structured FeSbO but interphase formation comprising antimony (oxy)fluorides is observed for MnSbO.

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The efficient conversion of solar energy to chemical energy represents a critical bottleneck to the energy transition. Photocatalytic splitting of water to generate solar fuels is a promising solution. Semiconductor quantum dots (QDs) are prime candidates for light-harvesting components of photocatalytic heterostructures, given their size-dependent photophysical properties and band-edge energies.

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Objectives: Total pancreatectomy with islet autotransplantation (TPIAT) is performed to improve the quality of life (QOL) of patients with chronic pancreatitis. Few reports have documented QOL following TPIAT, with none using the pancreatitis-specific Pancreatitis Quality of Life Instrument (PANQOLI). We surveyed patients at our center who underwent TPIAT to document postoperative QOL.

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Article Synopsis
  • This text discusses how the lone-pair electrons in p-block cations contribute to electronic and geometric structures, influencing properties like lattice anharmonicity and the stability of materials used in advanced technologies like nonlinear optics and thermoelectrics.
  • The authors explore the idea that by inserting these cations into interstitial sites within lattice structures, researchers can systematically control the electronic properties while maintaining the overall connectivity of the material.
  • The article investigates the effects of different cation types on lattice distortions and electronic structure, particularly focusing on how group 12 to group 14 cations affect properties through stereochemical activity and Jahn-Teller distortions.
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Objectives: Most patients receiving curative-intent surgery for pancreatic cancer will experience cancer recurrence. However, evidence that postoperative surveillance testing improves survival or quality of life is lacking. We evaluated the use and characteristics of surveillance with serial imaging and CA 19-9 tumor marker testing at an NCI-designated comprehensive cancer center.

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Stereoactive electron lone pairs derived from filled 5/6s states of p-block cations are an intriguing electronic and geometric structure motif that have been exploited for diverse applications such as thermoelectrics, thermochromics, photocatalysis, and nonlinear optics. Layered trivanadates are dynamic intercalation hosts, where the insertion of cations can be used to tune electron correlation, charge localization, and magnetic ordering. However, the interaction of 5/6s stereoactive electron lone pairs with layered trivanadates remains unexplored.

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Article Synopsis
  • Anaphylaxis is a severe allergic reaction, and immediate treatment with an epinephrine autoinjector (EAI) can save lives; physicians must choose the right EAI for individual patients and educate them for effective use.
  • A team of allergy experts reviewed data and guidelines to provide evidence-based recommendations for tailoring EAI selection, considering factors like individual needs, EAI properties, and costs.
  • While no EAI currently allows customization of dose or needle length, thoughtful prescribing can enhance the management of anaphylaxis by accommodating patient-specific variables.
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The fascinating adhesion of gecko to virtually any material has been related to surface interactions of myriads of spatula at the tips of gecko feet. Surprisingly, the molecular details of the surface chemistry of gecko adhesion are still largely unknown. Lipids have been identified within gecko adhesive pads.

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Lithium nickel manganese cobalt oxide (NMC) is a commercially successful Li-ion battery cathode due to its high energy density; however, its delivered capacity must be intentionally limited to achieve capacity retention over extended cycling. To design next-generation NMC batteries with longer life and higher capacity the origins of high potential capacity fade must be understood. hard X-ray characterization techniques are critical for this endeavor as they allow the acquisition of information about the evolution of structure, oxidation state, and coordination environment of NMC as the material (de)lithiates in a functional battery.

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Background: Total pancreatectomy with islet autotransplantation (TPIAT) requires a complex islet isolation process of the explanted pancreas. Islet isolation has historically required a specialized laboratory to perform islet isolation. We report our experience with a novel technique of intraoperative islet isolation that does not require a specialized islet laboratory, thereby making the isolation process simpler, more accessible, and less costly.

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The development of a cathode for solid-state lithium-oxygen batteries has been hindered in practice by a low capacity and limited cycle life despite their potential for high energy density. Here, a previously unexplored strategy is proposed wherein the cathode delivers a specific capacity of 200 milliampere hour per gram over 665 discharge/charge cycles, while existing cathodes achieve only ~50 milliampere hour per gram and ~100 cycles. A highly conductive ruthenium-based composite is designed as a carbon-free cathode by first-principles calculations to avoid the degradation associated with carbonaceous materials, implying an improvement in stability during the electrochemical cycling.

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Geckos have the astonishing ability to climb on vertical surfaces due to the adhesive properties of fibrous setae at the tips of their toe pads. While the adhesion mechanism principle, based on van der Waals interactions of myriads of spatula located at the outermost end of the setal arrays, has been studied extensively, there are still open questions about the chemistry of gecko setae. The gecko adhesive system is based on keratin fibrils assembled to support the entire setal structure.

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We present the design and performance of a polarized resonant soft x-ray scattering (RSoXS) station for soft matter characterization built by the national institute of standards and technology at the national synchrotron light source-II (NSLS-II). The RSoXS station is located within the spectroscopy soft and tender beamline suite at NSLS-II located in Brookhaven national laboratory, New York. Numerous elements of the RSoXS station were designed for optimal performance for measurements on soft matter systems, where it is of critical importance to minimize beam damage and maximize collection efficiency of polarized x-rays.

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Neoadjuvant therapy is increasingly being used for localized pancreatic adenocarcinoma. While there is evidence supporting neoadjuvant systemic chemotherapy as well as chemoradiation, more evidence is needed to determine whether systemic chemotherapy with chemoradiation offers benefits over chemoradiation alone. This study compares the outcomes of neoadjuvant chemoradiation therapy with and without systemic chemotherapy in resectable and borderline resectable pancreatic cancers.

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First-principles, real-time-cumulant, and Bethe-Salpeter-equation calculations fully capture the detailed satellite structure that occurs in response to the sudden creation of the core hole in both photoemission and x-ray absorption spectra of the transition-metal compounds SrTiO and rutile TiO. Analysis of the excited-state, real-space charge-density fluctuations betrays the physical nature of these many electron excitations that are shown to reflect the materials' solid-state electronic structure and chemical bonding. This first-principles development of the cumulant-based core hole spectral function is generally applicable to other systems and should become a standard tool for all similar spectroscopic analysis going beyond the quasiparticle physics of the photoelectric effect.

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A stereocontrolled synthesis of , the C(10)-C(25) component of amphidinolide C (), has been efficiently achieved. Reaction of the dithiane component with nonracemic bis(epoxide) directly affords functionalized 2,5--disubstituted tetrahydrofuran . Propargylation is highly diastereoselective for the formation of the desired C(12)-C(13) stereochemistry, and the resulting terminal alkyne is utilized for a regioselective -silylstannylation.

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Actin-based tubular connections between cells have been observed in many cell types. Termed "tunneling nanotubes (TNTs)," "membrane nanotubes," "tumor microtubes (TMTs)," or "cytonemes," these protrusions interconnect cells in dynamic networks. Structural features in these protrusions vary between cellular systems, including tubule diameter and the presence of microtubules.

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Currently, testing for immunoglobulin E (IgE) sensitization is the cornerstone of diagnostic evaluation in suspected allergic conditions. This review provides a thorough and updated critical appraisal of the most frequently used diagnostic tests, both and . It discusses skin tests, challenges, and serological and cellular tests, and provides an overview of indications, advantages and disadvantages of each in conditions such as respiratory, food, venom, drug, and occupational allergy.

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Black carbon (BC) absorbs solar radiation, leading to a strong but uncertain warming effect on climate. A key challenge in modeling and quantifying BC's radiative effect on climate is predicting enhancements in light absorption that result from internal mixing between BC and other aerosol components. Modeling and laboratory studies show that BC, when mixed with other aerosol components, absorbs more strongly than pure, uncoated BC; however, some ambient observations suggest more variable and weaker absorption enhancement.

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Short, strong hydrogen bonds (SSHBs) have been a source of interest and considerable speculation over recent years, culminating with those where hydrogen resides around the midpoint between the donor and acceptor atoms, leading to quasi-covalent nature. We demonstrate that X-ray photoelectron spectroscopy (XPS) and near-edge X-ray absorption fine structure (NEXAFS) spectroscopy provide deep insight into the electronic structure of the short OHN hydrogen bond of 3,5-pyridinedicarboxylic acid, revealing for the first time distinctive spectroscopic identifiers for these quasi-symmetrical hydrogen bonds. An intermediate nitrogen (core level) chemical shift occurs for the almost centrally located hydrogen compared to protonated (ionic) and non-ionic analogues, and it reveals the absence of two-site disorder.

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The outermost surface of insect cuticle is a high-performance interface that provides wear protection, hydration, camouflage and sensing. The complex and inhomogeneous structure of insect cuticle imposes stringent requirements on approaches to elucidate its molecular structure and surface chemistry. Therefore, a molecular understanding and possible mimicry of the surface of insect cuticle has been a challenge.

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