Within archaeological studies of ancient pottery, understanding the techniques used to form vessels from unfired clay provides significant information on the history of technology and economic systems, as well as wider cultural practices and social interactions. We introduce here a new analytical methodology, using small-angle neutron scattering (SANS) to investigate pottery forming techniques through the preferential orientation of nanoscale objects within pottery fabrics. Significantly, SANS is non-destructive, suitable for both coarse and fine-textured pottery fabrics, provides quantitative data, enables fast-throughput of samples, and is not significantly affected by surface modifications occurring after the primary forming stage.
View Article and Find Full Text PDFPresented here is an effective approach to desmearing slit ultra-small-angle neutron scattering (USANS) data, based on complementary small-angle neutron scattering (SANS) measurements, leading to a seamless merging of these data sets. The study focuses on the methodological aspects of desmearing USANS data, which can then be presented in the conventional manner of SANS, enabling a broader pool of data analysis methods. The key innovation lies in the use of smeared SANS data for extrapolating slit USANS, offering a self-consistent integrand function for desmearing with Lake's iterative method.
View Article and Find Full Text PDFThe co-assembly of polyelectrolytes (PE) with proteins offers a promising approach for designing complex structures with customizable morphologies, charge distribution, and stability for targeted cargo delivery. However, the complexity of protein structure limits our ability to predict the properties of the formed nanoparticles, and our goal is to identify the key triggers of the morphological transition in protein/PE complexes and evaluate their ability to encapsulate multivalent ionic drugs. A positively charged PE can assemble with a protein at pH above isoelectric point due to the electrostatic attraction and disassemble at pH below isoelectric point due to the repulsion.
View Article and Find Full Text PDFSurface chemistry of materials that host quantum bits such as diamond is an important avenue of exploration as quantum computation and quantum sensing platforms mature. Interfacing diamond in general and nanoscale diamond (ND) in particular with silica is a potential route to integrate room temperature quantum bits into photonic devices, fiber optics, cells, or tissues with flexible functionalization chemistry. While silica growth on ND cores has been used successfully for quantum sensing and biolabeling, the surface mechanism to initiate growth was unknown.
View Article and Find Full Text PDFZr-based metal-organic framework materials (Zr-MOFs) with increased specific surface area and pore volume were obtained using chemical (two materials, and ) and solvothermal () synthesis methods and investigated via FT-IR spectroscopy, TGA, SANS, PXRD, and SEM methods. The difference between and lies in the addition of reactants during synthesis. Nitrogen porosimetry data indicated the presence of pores with average dimensions of ~4 nm; using SANS, the average size of the nanocrystals was suggested to be approximately 30 nm.
View Article and Find Full Text PDFWe report on the morphological transitions of didodecyldimethylammonium bromide (DDAB) cationic vesicles and hybrid DDAB/hyaluronic acid (HA) vesicles upon addition of BSA at pH 7 where BSA is overall negatively charged. Small angle neutron scattering (SANS) is used to extract the size distributions of the nanovesicles, the thickness of the DDAB bilayers and their lamellarity. Although the HA-decorated DDAB vesicles contain the negatively charged polysaccharide the interaction with BSA appears to be more intense in comparison to bare vesicles.
View Article and Find Full Text PDFComposite silica xerogels were prepared via acid catalysed sol-gel route using tetraethoxysilan (TEOS) as silica precursor, and 1-butyl-3-methylimidazolium tetrafluoroborate [BMIM][BF] or 1-butyl-3-methylimidazolium chloride [BMIM][Cl] ionic liquids, used simultaneously as co-solvents, catalysts and pore templates, at various IL-to-silica ratios. Morphology of the xerogels prepared using the different IL templating agents were investigated using scanning electron microscopy (SEM), nitrogen sorption and small angle neutron scattering (SANS). The thermal behavior of the composites was analyzed by thermal gravimetry, whereas the compositions were checked by infrared spectroscopy and EDX.
View Article and Find Full Text PDFNanomaterials (Basel)
March 2021
ACS Appl Mater Interfaces
January 2021
The most relevant properties of polysaccharide aerogels in practical applications are determined by their microstructures. Hydration has a dominant role in altering the microstructures of these hydrophilic porous materials. To understand the hydration induced structural changes of monolithic Ca-alginate aerogel, produced by drying fully cross-linked gels with supercritical CO, the aerogel was gradually hydrated and characterized at different states of hydration by small-angle neutron scattering (SANS), liquid-state nuclear magnetic resonance (NMR) spectroscopy, and magic angle spinning (MAS) NMR spectroscopy.
View Article and Find Full Text PDFDue to their effect of vasodilatation, isosorbide nitrates represent one of the most important and most used solutions for angina pectoris. Unfortunately, these compounds have multiple dose-related adverse drug reactions such as headache, weakness, mild dizziness, and occasionally heart rate changes, nausea, vomiting, and sweating. The main aims of this research were to obtain and to evaluate new polyurethane (PU) structures that can be used as a proper transmembrane carrier with an improved release kinetic.
View Article and Find Full Text PDFFemale entertainment and sex workers (FESW) are vulnerable to violence, which impedes safer sex behaviors and increases risk of HIV. FESW are also disproportionately affected by co-occurring psychosocial health conditions, including substance use, depression, and economic insecurity, which increased risk of exposure to violence. We used a syndemic framework to examine the effects of co-occurring psychosocial conditions on the risk of client-perpetrated physical and sexual violence against FESW.
View Article and Find Full Text PDFPhys Occup Ther Pediatr
February 2021
Aims: Children with idiopathic toe walking (ITW) gait are increasingly referred to physical therapists. The purpose of this study was to evaluate the intra-rater and inter-rater reliability of the Clinical Gait Assessment Scale (CGAS), a newly developed observational rating scale.
Methods: Four raters evaluated videos of four children.
A facile sol-gel route has been applied to synthesize hybrid silica-PVA-iron oxide nanocomposite materials. A step-by-step calcination (processing temperatures up to 400 °C) was applied in order to oxidize the organics together with the iron precursor. Transmission electron microscopy, X-ray diffraction, small angle neutron scattering, and nitrogen porosimetry were used to determine the temperature-induced morpho-textural modifications.
View Article and Find Full Text PDFSilica-gelatin hybrid aerogels of varying gelatin content (from 4 wt.% to 24 wt.%) can be conveniently impregnated with hydrophobic active agents (e.
View Article and Find Full Text PDFPurpose: Red chili peppers have been highly valued in gastronomy and traditional medicine since ancient times; it seems that it is not just an ingredient for food but also a good remedy for various medical conditions such as increased blood pressure and high levels of serum triglycerides and cholesterol, myocardial infarction, arthritis, and migraines. The objective of this study is the characterization of a new carrier used for encapsulated extract.
Methods: Chili pepper extract was obtained and was physically entrapped inside polyurethane microparticles in order to diminish the irritative potential of this extract.
This work is focused on a novel class of hybrid materials exhibiting enhanced optical properties and high surface areas that combine the morphology offered by the vinyl substituted silica host, and the excellent absorption and emission properties of 5,10,15,20-tetrakis(-methyl-4-pyridyl)porphyrin-Zn(II) tetrachloride as a water soluble guest molecule. In order to optimize the synthesis procedure and the performance of the immobilized porphyrin, silica precursor mixtures of different compositions were used. To achieve the requirements regarding the hydrophobicity and the porous structure of the gels for the successful incorporation of porphyrin, the content of vinyltriacetoxysilane was systematically changed and thoroughly investigated.
View Article and Find Full Text PDFBackground: HIV prevalence remains high in Cambodia among female entertainment and sex workers (FESW), and amphetamine-type stimulant (ATS) use significantly increases risk of infection. A successful continuum of care (CoC) is key to effective clinical care and prevention. This study aimed to describe the HIV CoC in HIV-positive FESW.
View Article and Find Full Text PDFPiperidine and N-methylpiperidine hydrates aggregate in liquid aqueous solutions due to hydrogen bonds between hydration water molecules. No such effects occur in the mixtures of the amines with methanol, that supports the idea of active role of water solvent in the aggregation. However, the question of contributions in thermodynamic functions due to specific interactions, van der Waals forces, and the size and shape of the molecules remains open.
View Article and Find Full Text PDFSpontaneous or traumatic hemorrhages into joints that occur in the course of congenital bleeding disorders due to deficiencies of plasma clotting factors lead to early and extensive damage to joints. Arthropathy in those patients most commonly affects the knee, elbow and ankle. Replacement surgery of the damaged joint is the only effective way to treat such advanced changes.
View Article and Find Full Text PDFHIV-1 spreads between CD4 T cells most efficiently through virus-induced cell-cell contacts. To test whether this process potentiates viral spread by activating signaling pathways, we developed an approach to analyze the phosphoproteome in infected and uninfected mixed-population T cells using differential metabolic labeling and mass spectrometry. We discovered HIV-1-induced activation of signaling networks during viral spread encompassing over 200 cellular proteins.
View Article and Find Full Text PDFObjectives/hypothesis: To describe the pathophysiology of horizontal canal benign paroxysmal positional vertigo, the available maneuvers for its management, and the recommended treatment.
Data Sources: PubMed, Cochrane library.
Review Methods: Review of the available literature.
The envelope glycoprotein (Env) of the Human Immunodeficiency Virus Type-1 (HIV-1) is a critical determinant of viral infectivity, tropism and is the main target for humoral immunity; however, little is known about the cellular machinery that directs Env trafficking and its incorporation into nascent virions. Here we identify the mammalian retromer complex as a novel and important cellular factor regulating Env trafficking. Retromer mediates endosomal sorting and is most closely associated with endosome-to-Golgi transport.
View Article and Find Full Text PDF