Working Conditions for Burns Resident Doctors-Better Now than Ever?

Background: The work and life of a resident (or "junior") doctor has changed dramatically over the past 50 years. Descriptions of historic working conditions are usually anecdotal and tinted with nostalgia, but do today's burns and plastic surgery doctors feel working conditions have improved or declined over the last 50 years, and does this have an impact on recruitment and retention?

Methods: An interview was conducted with a retired surgeon who, in 1970, worked as a house surgeon (Year 2 doctor equivalent) in a burns unit for the pioneering burn surgeon Mr. Douglas MacGregor Jackson.

Film Thickness Dependent Stability and Glass Transition Temperature of Polymer Films Produced by Physical Vapor Deposition.

We report measurements of the onset temperature of rejuvenation, T_{onset}, and the fictive temperature, T_{f}, for ultrathin stable polystyrene with thicknesses from 10 to 50 nm prepared by physical vapor deposition. We also measure the T_{g} of these glasses on the first cooling after rejuvenation as well as the density anomaly of the as-deposited material. Both the T_{g} in rejuvenated films and the T_{onset} in stable films decrease with decreasing film thickness.

Surface and bulk relaxation of vapor-deposited polystyrene glasses.

We have studied the liquid-like response of the surface of vapor-deposited glassy films of polystyrene to the introduction of gold nanoparticles on the surface. The build-up of polymer material was measured as a function of time and temperature for both as-deposited films, as well as films that have been rejuvenated to become normal glasses cooled from the equilibrium liquid. The temporal evolution of the surface profile is well described by the characteristic power law of capillary-driven surface flows.

On the bridge hypothesis in the glass transition of freestanding polymer films.

Freestanding thin polymer films with high molecular weights exhibit an anomalous decrease in the glass-transition temperature with film thickness. Specifically, in such materials, the measured glass-transition temperature evolves in an affine way with the film thickness, with a slope that weakly depends on the molecular weight. De Gennes proposed a sliding mechanism as the hypothetical dominant relaxation process in these systems, where stress kinks could propagate in a reptation-like fashion through so-called bridges, i.

Nanoscale surface roughness induced by poor solvents on polymer film surfaces.

We describe a new nanoscale morphology that is produced when polymer surfaces are exposed to a poor solvent. We have measured the morphology on polystyrene surfaces after exposure to pentane, heptane, or dodecane as well as poly(methyl methacrylate) exposed to propanol or methanol. The length scale of the morphology was determined by analyzing images obtained by atomic force microscopy.

Seroprevalence of SARS-CoV-2 antibodies in front-line pediatric health care workers.

Objective: The goal of this study was to determine the prevalence of SARS-CoV-2 infections in pediatric front-line health care workers (HCWs) using SARS-CoV-2 serum antibodies as an indicator of infection.

Methods: In this cross-sectional study, we collected blood samples and survey responses from HCWs in a 38-bed pediatric emergency department. Serum antibodies to SARS-CoV-2 (IgM and/or IgG) were measured using a 2-step enzyme-linked immunosorbent assay (ELISA) to detect antibodies against the Spike protein receptor binding domain (RBD), the ectodomain of Spike (S), and the nucleoprotein (N).

A β-NMR study of the depth, temperature, and molecular-weight dependence of secondary dynamics in polystyrene: Entropy-enthalpy compensation and dynamic gradients near the free surface.

We investigated the depth, temperature, and molecular-weight (MW) dependence of the γ-relaxation in polystyrene glasses using implanted Li and β-detected nuclear magnetic resonance. Measurements were performed on thin films with MW ranging from 1.1 to 641 kg/mol.

Anisotropy and anharmonicity in polystyrene stable glass.

We have used ellipsometry to characterize the anisotropy in stable polymer glasses prepared by physical vapor deposition. These measurements reveal birefringence values (as measured by the magnitude of in-plane vs out-of-plane refractive index) less than 0.002 in vapor-deposited polystyrenes with N from 6 to 12 and with fictive temperatures between 10 K and 35 K below the T values.

Crystallization and melting of highly monodisperse poly(ethylene-oxide).

We present a quantitative study of the crystallization and melting behaviours of highly monodisperse PEO oligomers, and compare to previous studies. Through evaporative purification, we were able to isolate low molecular weight PEO oligomers that are much more monodisperse than the as-purchased material (as measured by mass spectrometry). Crystal structure, crystal growth rate and melting temperatures were characterized.

Author Correction: R-loop-forming Sequences Analysis in Thousands of Viral Genomes Identify A New Common Element in Herpesviruses.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

The potential impacts of early secreted antigenic target of 6 kDa of Mycobacterium tuberculosis on KSHV-infected cells.

Kaposi's sarcoma-associated herpesvirus (KSHV) causes several human cancers, including Kaposi's sarcoma (KS) and primary effusion lymphoma, which are mostly seen in immunocompromised patients, such as human immunodefeciency virus (HIV)+ individuals. Tuberculosis (TB), caused by the bacterial pathogen Mycobacterium tuberculosis (Mtb), remains one of the deadliest infectious diseases in the world. The risk of developing TB is dramatically higher in people living with HIV than among those without HIV infection.

Ultrastable monodisperse polymer glass formed by physical vapour deposition.

Stable glasses prepared by vapour deposition are an analogue of glassy materials aged for geological timescales. The ability to prepare such materials allows the study of near-ideal glassy systems. We report the preparation and characterization of stable glasses of polymers prepared by physical vapour deposition.

Cooperative strings and glassy dynamics in various confined geometries.

Previously, we developed a minimal model based on random cooperative strings for the relaxation of supercooled liquids in the bulk and near free interfaces, and we recovered some key experimental observations. In this article, after recalling the main ingredients of the cooperative string model, we study the effective glass transition and surface mobility of various experimentally relevant confined geometries: freestanding films, supported films, spherical particles, and cylindrical particles, with free interfaces and/or passive substrates. Finally, by canceling and restarting any cooperative-chain realization reaching the boundary with a smaller number of steps than the bulk cooperativity, we account for a purely attractive substrate, and explore the impact of the latter in the previous geometries.

R-loop-forming Sequences Analysis in Thousands of Viral Genomes Identify A New Common Element in Herpesviruses.

R-loops are RNA-DNA hybrid sequences that are emerging players in various biological processes, occurring in both prokaryotic and eukaryotic cells. In viruses, R-loop investigation is limited and functional importance is poorly understood. Here, we performed a computational approach to investigate prevalence, distribution, and location of R-loop forming sequences (RLFS) across more than 6000 viral genomes.

Crystallization of low molecular weight atactic polystyrene.

We observe and characterize the crystallization of atactic polystyrenes (PS) of nearly oligomeric M using atomic force microscopy. We find that the low M polystyrene exhibits observable crystals on the surface. The crystals appear to be a few nm thick and nm to microns wide.

Direct measurements of the temperature, depth and processing dependence of phenyl ring dynamics in polystyrene thin films by β-detected NMR.

There is indirect evidence that the dynamics of a polymer near a free surface are enhanced compared with the bulk but there are few studies of how dynamics varies with depth. β-Detected nuclear spin relaxation of implanted 8Li+ has been used to directly probe the temperature and depth dependence of the γ-relaxation mode, which is due to phenyl rings undergoing restricted rotation, in thin films of atactic deuterated polystyrene (PS-d8) and determine how the depth dependence of dynamics is affected by sample processing, such as annealing, floating on water and the inclusion of a surfactant, and by the presence of a buried interface. The activation energy for the γ-relaxation process is lower near the free surface.

Correction: Cooperative strings in glassy nanoparticles.

Correction for 'Cooperative strings in glassy nanoparticles' by Maxence Arutkin et al., Soft Matter, 2017, 13, 141-146.

A randomized comparative evaluation of clinical and home application to investigate the effectiveness of silver nitrate (AgNO ) (95%) for the treatment of verruca pedis.

Objective: To investigate the clinical effectiveness of silver nitrate (95%) for the treatment of verruca pedis comparing professional and self-application treatments.

Methods: A single-centre, two-armed randomized evaluation was conducted at a University podiatry clinic. A total of 113 participants (101 analysed) with verruca pedis were included.

A Review of Techniques to Measure Protein Sorption to Soft Contact Lenses.

Purpose: To compare and critically evaluate a variety of techniques to measure the quantity and biological activity of protein sorption to contact lenses over short time periods.

Methods: A literature review was undertaken investigating the major techniques to measure protein sorption to soft contact lens materials, with specific reference to measuring protein directly on lenses using in situ, ex situ, protein structural, and biological activity techniques.

Results: The use of in situ techniques to measure protein quantity provides excellent sensitivity, but many are not directly applicable to contact lenses.

Controlling Marangoni-induced instabilities in spin-cast polymer films: How to prepare uniform films.

In both research and industrial settings spincoating is extensively used to prepare highly uniform thin polymer films. However, under certain conditions, spincoating results in films with non-uniform surface morphologies. Although the spincoating process has been extensively studied, the origin of these morphologies is not fully understood and the formation of non-uniform spin-cast films remains a practical problem.

Cooperative strings in glassy nanoparticles.

Motivated by recent experimental results on glassy polymer nanoparticles, we develop a minimal theoretical framework for the glass transition in spherical confinement. This is accomplished using our cooperative-string model for supercooled dynamics, that was successful at recovering the bulk phenomenology and describing the thin-film anomalies. In particular, we obtain predictions for the mobile-layer thickness as a function of temperature, and for the effective glass-transition temperature as a function of the radius of the spherical nanoparticle - including the existence of a critical particle radius below which vitrification never occurs.

Controlling the Morphology of Organic Crystals with Filamentous Bacteriophages.

The preparation of thiamethoxam (TMX) organic crystals with high morphological uniformity was achieved by controlled aggregation-driven crystallization of primitive TMX crystals and phage using the filamentous M13 bacteriophage. The development of a regular, micrometer-sized, tetragonal-bipyramidal crystal structure was dependent on the amount of phage present. The phage appears to affect the supersaturation driving force for crystallization.

Cooperative strings and glassy interfaces.

We introduce a minimal theory of glass formation based on the ideas of molecular crowding and resultant string-like cooperative rearrangement, and address the effects of free interfaces. In the bulk case, we obtain a scaling expression for the number of particles taking part in cooperative strings, and we recover the Adam-Gibbs description of glassy dynamics. Then, by including thermal dilatation, the Vogel-Fulcher-Tammann relation is derived.

Analysis of Using I(125) Radiolabeling for Quantifying Protein on Contact Lenses.

Purpose: To investigate the accuracy of I(125) radiolabeling to quantitatively determine the deposition of protein onto various commercially available contact lens (CL) materials.

Methods: Commercially available silicone hydrogel and conventional hydrogel CL materials were examined for times ranging from 10 s to 1 week. Adsorption of free I(125) was measured directly for the CL.

Competitive Effects from an Artificial Tear Solution to Protein Adsorption.

Purpose: To compare the adsorption of lysozyme, lactoferrin, and albumin to various contact lens materials, between single-protein solutions and a multicomponent artificial tear solution (ATS). Additionally, extra steps were taken to distinguish loosely and tightly bound protein, the latter of which may be fully or partially denatured.

Methods: Using a previously described ATS, we measured the time-dependent adsorption of lys, lac, and alb onto one conventional hydrogel and four silicone hydrogel contact lens materials between the first minute and up to 1 week of protein interaction with the material surface.