Experimental observation and characterization of amorphous carbon generated in graphene on gold nanoparticles.

The interaction of graphene with gold nanoparticles is investigated using transmission electron microscopy. We observe gold-nanoparticle-mediated etching of graphene flakes, often leading to hole formation. Further, using a combination of high-angle annular dark field imaging and electron energy loss spectroscopy, we highlight that the catalytic effects of gold nanoparticles on graphene lead to the formation of amorphous carbon layers.

The effect of comb length on the and properties of self-assembled poly(oligoethylene glycol methacrylate)-based block copolymer nanoparticles.

Comb copolymer analogues of poly(lactic acid)-polyethylene glycol block copolymers (PLA--PEG) offer potential to overcome the inherent chemistry and stability limitations of their linear block copolymer counterparts. Herein, we examine the differences between P(L)LA--PEG and linear-comb copolymer analogues thereof in which the linear PEG block is replaced by poly(oligo(ethylene glycol) methacrylate) (POEGMA) blocks with different side chain (comb) lengths but the same overall molecular weight. P(L)LA--POEGMA475 and P(L)LA--POEGMA2000 block copolymers were synthesized activators regenerated by electron transfer atom transfer radical polymerization (ARGET ATRP) and fabricated into self-assembled nanoparticles using flash nanoprecipitation confined impinging jet mixing.

Experiences of insecurity among non-standard workers across different welfare states: A qualitative cross-country study.

In recent decades, economic crises and political reforms focused on employment flexibilization have increased the use of non-standard employment (NSE). National political and economic contexts determine how employers interact with labour and how the state interacts with labour markets and manages social welfare policies. These factors influence the prevalence of NSE and the level of employment insecurity it creates, but the extent to which a country's policy context mitigates the health influences of NSE is unclear.

Prognostic Association Between Frailty and Post-Arrest Health Outcomes in Patients Receiving Home Care: A Population-Based Retrospective Cohort Study.

Aim: To evaluate the association between frailty and post-cardiac arrest survival, functional decline, and cognitive decline, among patients receiving home care.

Methods: Frailty was measured using the Clinical Frailty Scale (CFS) and a valid frailty index. We used multivariable logistic regression to measure the association between frailty and post-arrest outcomes after adjusting for age, sex, and arrest setting.

Uranium(iv) alkyl cations: synthesis, structures, comparison with thorium(iv) analogues, and the influence of arene-coordination on thermal stability and ethylene polymerization activity.

Reaction of [(XA)U(CHSiMe)] (1; XA = 4,5-bis(2,6-diisopropylanilido)-2,7-di--butyl-9,9-dimethylxanthene) with 1 equivalent of [PhC][B(CF)] in arene solvents afforded the arene-coordinated uranium alkyl cations, [(XA)U(CHSiMe)(η -arene)][B(CF)] {arene = benzene (2), toluene (3), bromobenzene (4) and fluorobenzene (5)}. Compounds 2, 3, and 5 were crystallographically characterized, and in all cases the arene is π-coordinated. Solution NMR studies of 2-5 suggest that the binding preferences of the [(XA)U(CHSiMe)] cation follow the order: toluene ≈ benzene > bromobenzene > fluorobenzene.

Prognosis of cardiac arrest in home care clients and nursing home residents: A population-level retrospective cohort study.

Aim: To evaluate the prognosis of 30-day survival post-cardiac arrest among patients receiving home care and nursing home residents.

Methods: We conducted a population-level retrospective cohort study of community-dwelling adults (≥18 years) who received cardiac arrest care at a hospital in Ontario, Canada, between 2006 to 2018. We linked population-based health datasets using the Home Care Dataset to identify patients receiving home care and the Continuing Care Reporting System to identify nursing home residents.

Compatibilization of porphyrins for use as high permittivity fillers in low voltage actuating silicone dielectric elastomers.

Polysiloxanes represent, because of their unusual properties, a material with great potential for use in dielectric elastomers (DEs), a promising class of electroactive polymers. Currently, their application as actuators is limited by the need for high driving voltages, as a result of the low relative permittivity possessed by polysiloxanes (∼2-3). Reducing these voltages can be achieved to some degree by using high permittivity additives to improve the permittivity of the polysiloxane.

Time Evolution of Correlation Functions in Quantum Many-Body Systems.

We give rigorous analytical results on the temporal behavior of two-point correlation functions-also known as dynamical response functions or Green's functions-in closed many-body quantum systems. We show that in a large class of translation-invariant models the correlation functions factorize at late times ⟨A(t)B⟩_{β}→⟨A⟩_{β}⟨B⟩_{β}, thus proving that dissipation emerges out of the unitary dynamics of the system. We also show that for systems with a generic spectrum the fluctuations around this late-time value are bounded by the purity of the thermal ensemble, which generally decays exponentially with system size.

Assessing size-dependent cytotoxicity of boron nitride nanotubes using a novel cardiomyocyte AFM assay.

As boron nitride nanotubes (BNNTs) find increased use in numerous applications, potential adverse health effects of BNNT exposure are a growing concern. Current cytotoxicity studies on BNNTs are inconsistent and even contradictory, likely due to the lack of reference materials, standardized characterization methods and measurement protocols. New approaches, particularly with the potential to reliably relate to studies, are critically needed.

The impact of processing on the cytotoxicity of graphene oxide.

In-house prepared graphene oxide (GO) was processed base washing, sonication, cleaning and combinations of these processing techniques to evaluate the impact on the flake morphology, composition and cytotoxicity of the material. The flakes of unprocessed GO were relatively planar, but upon base washing, the flakes became textured exhibiting many folds and creases observed by AFM. In addition to the pronounced effect on the topography, base washing increased the C/O ratio and increased the cytotoxicity of GO on all four cell lines studied determined the WST-8 assay.

Intramedullary Nailing Versus Plate Fixation for the Treatment Displaced Midshaft Clavicular Fractures: A Systematic Review and Meta-Analysis.

The two commonly performed surgical techniques used to repair displaced midshaft clavicle fractures are plate fixation or intramedullary nailing; however, despite recent evidence, the optimal method to treat such fractures remains a continued topic of debate. A meta-analysis of randomized controlled trials (RCTs) was conducted to evaluate long term function, complications, and operative duration in adult patients receiving intramedullary nailing in comparison to plating. Seven RCTs and three quasi-randomized trials were included.

Properties of Poly(ethylene glycol) Hydrogels Cross-Linked via Strain-Promoted Alkyne-Azide Cycloaddition (SPAAC).

A series of poly(ethylene glycol) (PEG) hydrogels was synthesized using strain-promoted alkyne-azide cycloaddition (SPAAC) between PEG chains terminated with either aza-dibenzocyclooctynes or azide functionalities. The gelation process was found to occur rapidly upon mixing the two components in aqueous solution without the need for external stimuli or catalysts, making the system a candidate for use as an injectable hydrogel. The mechanical and rheological properties of these hydrogels were found to be tunable by varying the polymer molecular weight and the number of cross-linking groups per chain.

A Controlled Quasi-Experimental Study of an Educational Intervention to Reduce the Unnecessary Use of Antimicrobials For Asymptomatic Bacteriuria.

Background: Asymptomatic bacteriuria (ABU) should only be treated in cases of pregnancy or in-patients undergoing urologic procedures; however, unnecessary treatment of ABU is common in clinical practice.

Objective: To identify risk factors for unnecessary treatment and to assess the impact of an educational intervention focused on these risk factors on treatment of ABU.

Design: Quasi-experimental study with a control group.

Dietary amelioration of locomotor, neurotransmitter and mitochondrial aging.

Aging degrades motivation, cognition, sensory modalities and physical capacities, essentially dimming zestful living. Bradykinesis (declining physical movement) is a highly reliable biomarker of aging and mortality risk. Mice fed a complex dietary supplement (DSP) designed to ameliorate five mechanisms associated with aging showed no loss of total daily locomotion compared with >50% decrement in old untreated mice.

Impact of microgel morphology on functionalized microgel-drug interactions.

The interactions of a range of water-soluble drugs of different charges and hydrophobicities with carboxylic acid-functionalized poly(N-isopropylacrylamide)-based microgels containing different functional group distributions are investigated to determine the impact of drug properties and microgel morphologies on drug uptake and release. The radial distribution of carboxylic acid functional groups in the microgel and the hydrophobicities of the cationic drugs both strongly affect drug partitioning between the solution and microgel phases. Microgels with surface-localized functional group distributions bind less cationic drug than bulk-functionalized microgels, likely due to the formation of a locally collapsed "skin layer" at the acid-base drug binding sites at the microgel surface.