Dextran-Encapsulated Nanoparticles and Super-Nanoparticle Assemblies: Preparation from Quantum Dots, Fluorescent Polymers, and Magnetic Nanoparticles for Application to Cellular Immunolabeling.

Nanoparticles (NPs) continue to be developed as labels for bioanalysis and imaging due to their small size and, in many cases, emergent properties such as photoluminescence (PL) and superparamagnetism. Some applications stand to benefit from amplification of the advantageous properties of a NP, but this amplification is not a simple matter of scaling for size-dependent properties. One promising approach to amplification is, therefore, to assemble many copies of a NP into a larger but still nanoscale and colloidal entity.

In Vivo Optical Clearing of Mammalian Brain.

Established methods for imaging the living mammalian brain have, to date, taken optical properties of the tissue as fixed; we here demonstrate that it is possible to modify the optical properties of the brain itself to significantly enhance at-depth imaging while preserving native physiology. Using a small amount of any of several biocompatible materials to raise the refractive index of solutions superfusing the brain prior to imaging, we could increase several-fold the signals from the deepest cells normally visible and, under both one-photon and two-photon imaging, visualize cells previously too dim to see. The enhancement was observed for both anatomical and functional fluorescent reporters across a broad range of emission wavelengths.

Unmasking Fluorinated Moieties on the Surface of Hydride-Terminated Silicon Nanoparticles.

Despite the widespread use of hydrofluoric acid (HF) in the preparation of silicon surfaces, the true nature of fluorinated surface species remains unclear. Here, we employ an array of characterization techniques led by solid-state nuclear magnetic resonance spectroscopy to uncover the nature of fluorinated moieties on the surface of hydride-terminated silicon nanoparticles (H-SiNPs). A structural model that explains the observed trends in F and Si magnetic shielding is proposed and further supported by quantum chemical computations.

Managing "socially admitted" patients in hospital: a qualitative study of health care providers' perceptions.

Background: Emergency departments are a last resort for some socially vulnerable patients without an acute medical illness (colloquially known as "socially admitted" patients), resulting in their occupation of hospital beds typically designated for patients requiring acute medical care. In this study, we aimed to explore the perceptions of health care providers regarding patients admitted as "social admissions."

Methods: This qualitative study was informed by grounded theory and involved semistructured interviews at a Nova Scotia tertiary care centre.

Introduction to fundamental processes in optical nanomaterials.

An introduction to the joint and themed collection focused on fundamental processes in optical nanomaterials that features a series of articles describing the properties of this versatile class of materials while highlighting some of their potential applications.

Synthesis of high-entropy germanides and investigation of their formation process.

High-entropy alloys and compounds have emerged as an attractive research area in part because of their distinctive solid-solution structure and multi-element compositions that provide near-limitless tailorability. A diverse array of reports describing high-entropy compounds, including carbides, nitrides, sulfides, oxides, fluorides, silicides, and borides, has resulted. Strikingly, exploration of high-entropy germanides (HEGs) has remained relatively limited.

Not all silicon quantum dots are equal: photostability of silicon quantum dots with and without a thick amorphous shell.

Luminescent colloidal silicon quantum dots (SiQDs) are sustainable alternatives to metal-based QDs for various optical applications. While the materials are reliant on their photoluminescence efficiency, the relationship between the structure and photostability of SiQDs is yet to be well studied. An amorphous silicon (a-Si) shell was recently discovered in SiQDs prepared by thermally-processed silicon oxides.

Asphaltene-Derived Graphene Quantum Dots for Controllable Coatings on Glass, Fabrics, and Aerogels.

Graphene quantum dots (GQDs) derived from natural asphaltene byproducts can produce controlled hydrophobic or hydrophilic interfaces on glass, fabrics, and aerogels. A set of facile solvent extraction methods were used to isolate and chemically prepare materials with different surface functionalities from a commercially derived asphaltene precursor. The organic-soluble fraction was used to create hydrophobic and water-repellent surfaces on glass and cotton fabrics.

Understanding the Formation Mechanisms of Silicon Particles from the Thermal Disproportionation of Hydrogen Silsesquioxane.

Crystalline silicon particles sustaining Mie resonances are readily obtained from the thermal processing of hydrogen silsesquioxane (HSQ). Here, the mechanisms involved in silicon particle formation and growth from HSQ are investigated through real-time analysis using an environmental transmission electron microscope and X-ray diffractometer. The nucleation of Si nanodomains is observed starting around 1000 °C.

Consensus statement on the processing, interpretation and reporting of temporal artery biopsy for arteritis.

Giant cell arteritis (GCA) is the most common systemic vasculitis in adults in Europe and North America, typically involving the extra-cranial branches of the carotid arteries and the thoracic aorta. Despite advances in noninvasive imaging, temporal artery biopsy (TAB) remains the gold standard for establishing a GCA diagnosis. The processing of TAB depends largely on individual institutional protocol, and the interpretation and reporting practices vary among pathologists.

Spectrotemporal characterization of photoluminescent silicon nanocrystals and their energy transfer to dyes.

Silicon nanocrystals (SiNCs) are a promising material for applications in bioanalysis and imaging. Compared to other types of semiconductor nanocrystals, the development and characterization of energy transfer (ET) configurations with SiNCs has been far more limited, resulting in an equally limited understanding of this process and its SiNC-specific nuances. Here, we present a systematic and detailed study of ET between SiNCs and dyes.

Facile synthesis of high-entropy alloy nanoparticles on germanane, Ge nanoparticles and wafers.

The unique solid-solution structure and multi-element compositions of high-entropy alloy nanoparticles (HEA NPs) have garnered substantial attention. Various methods have been developed to prepare a diverse array of HEA NPs using different substrates for support and stabilization. In this study, we present a facile surface-mediated reduction method to prepare HEA NPs (AuAgCuPdPt) decorated germanane (HEA NPs@GeNSs), and employ X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM) to characterize their structure, composition, and morphology.

3D to 0D cesium lead bromide: A Br NMR, NQR and theoretical investigation.

Inorganic metal halides offer unprecedented tunability through elemental variation of simple three-element compositions, but can exhibit complicated phase behaviour, degradation, and microscopic phenomena (disorder/dynamics) that play an integral role for the bulk-level chemical and physical properties of these materials. Understanding the halogen chemical environment in such materials is crucial to addressing many of the concerns regarding implementing these materials in commercial applications. In this study, a combined solid-state nuclear magnetic resonance, nuclear quadrupole resonance and quantum chemical computation approach is used to interrogate the Br chemical environment in a series of related inorganic lead bromide materials: CsPbBr, CsPbBr, and CsPbBr.

Understanding silicon monoxide gas evolution from mixed silicon and silica powders.

Silicon on silica materials are ubiquitous in 21st century technology. From nanoparticles to integrated circuits, these systems are integral for modern semiconductor fabrication. While the Si-SiO interface is often (incorrectly) presumed to be stable, the direct reduction of silica by silicon is possible at high temperatures, resulting in the evolution of silicon monoxide (SiO) gas.

Metal nanoparticle-decorated germanane for selective photocatalytic aerobic oxidation of benzyl alcohol.

Two dimensional materials such as germanane have attracted substantial research interest due to their unique chemical, optical, and electronic properties. A variety of methods for introducing diverse functionalities to their surfaces have been reported and these materials have been exploited as photocatalysts. Herein, we report the preparation of metal nanoparticle (Au, Ag, Cu, Pd, Pt) decorated germanane (M@GeNSs) facile surface-mediated reduction and investigate their structure, composition, as well morphology using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM).

Ventricular Rupture at the Site of a Septic Myocardial Abscess After Acute Myocardial Infarction.

Mechanical complications after acute myocardial infarction are well-described yet catastrophic complications of acute coronary syndromes. Uniquely, we describe a rare case of left ventricular free wall rupture at the site of a septic myocardial abscess after an anterior wall myocardial infarction. ().

Myocarditis and endomyocardial biopsy: achieving consensus diagnosis on 100 cases.

The two histopathology benchmarks used to diagnose myocarditis are the Dallas Criteria, developed in 1984 and the European Society of Cardiology criteria, developed in 2013, which added immunohistochemistry for the detection of CD3+ T cells (lymphocytes) and CD68+ macrophages. Despite their near universal acceptance, the extent to which pathologists use these criteria or their own criteria to consistently render the diagnosis of myocarditis on endomyocardial biopsy (EMB) is unknown. We digitally scanned slides from 100 heart biopsies, including a trichrome stain and immunostaining, that were chosen as representative of myocarditis, non-myocarditis, and borderline myocarditis, as diagnosed per one institution's use of the Dallas Criteria.

Exploring Structural Nuances in Germanium Halide Perovskites Using Solid-State Ge and Cs NMR Spectroscopy.

Metal halide perovskites remain top candidates for higher-performance photovoltaic devices, but concerns about leading lead-based materials remain. Ge perovskites remain understudied for use in solar cells compared to their Sn-based counterparts. In this work, we undertake a combined Ge and Cs solid-state Nuclear Magnetic Resonance (NMR) spectroscopy and density functional theory (DFT) study of the bulk CsGeX (X = Cl, Br, or I) series.

Distinct networks of periaqueductal gray columns in pain and threat processing.

Noxious events that can cause physical damage to the body are perceived as threats. In the brainstem, the periaqueductal gray (PAG) ensures survival by generating an appropriate response to these threats. Hence, the experience of pain is coupled with threat signaling and interfaces in the dl/l and vlPAG columns.

Silicon Surface Passivation for Silicon-Colloidal Quantum Dot Heterojunction Photodetectors.

Sensitizing crystalline silicon (c-Si) with an infrared-sensitive material, such as lead sulfide (PbS) colloidal quantum dots (CQDs), provides a straightforward strategy for enhancing the infrared-light sensitivity of a Si-based photodetector. However, it remains challenging to construct a high-efficiency photodetector based upon a Si:CQD heterojunction. Herein, we demonstrate that Si surface passivation is crucial for building a high-performance Si:CQD heterojunction photodetector.

Tailoring B-doped silicon nanocrystal surface chemistry phosphorus pentachloride - mediated surface alkoxylation.

Doped silicon nanocrystals (SiNCs) are promising materials that could find use in a wide variety of applications. Realizing methods to tailor the surface chemistry of these particles offers greater tunability of the material properties as well as broader solvent compatibility. Herein, we report organic-soluble B-doped SiNCs prepared a thermal processing method followed by phosphorus pentachloride etching induced functionalization with alkoxy ligands of varied chain lengths.

"Turning the dials": controlling synthesis, structure, composition, and surface chemistry to tailor silicon nanoparticle properties.

Silicon nanoparticles (SiNPs) can be challenging to prepare with defined size, crystallinity, composition, and surface chemistry. As is the case for any nanomaterial, controlling these parameters is essential if SiNPs are to realize their full potential in areas such as alternative energy generation and storage, sensors, and medical imaging. Numerous teams have explored and established innovative synthesis methods, as well as surface functionalization protocols to control these factors.