Dynamics of hydrogen shift reactions between peroxy radicals.

Peroxy radicals are key intermediates in many atmospheric processes. Reactions between such radicals are of particular interest as they can lead to accretion products capable of participating in new particle formation (NPF). These reactions proceed through a tetroxide intermediate, which then decomposes to a complex of two alkoxy radicals and O, with spin conservation dictating that the complex must be formed in the triplet state.

Mechanistic Insights into the -Selective Catalytic Ring-Opening Metathesis Polymerization.

-selective ring-opening metathesis polymerization (ROMP) with the commercial Grubbs "nitrato catalyst" has shown promise for synthesizing stereoregular materials, but it comes with the drawback of losing control over the molecular weight due to the poor initiation rate of the catalyst and the need for stoichiometric ruthenium complex loading. To address these issues, we developed a chain transfer polymerization method that allows for the catalytic synthesis of polymers while controlling the degree of polymerization. This allowed us to produce shorter polymers with exceptional chain-end control.

Glutathione as a skin-lightening agent and in melasma: a systematic review.

Hyperpigmentary disorders, including melasma, are challenging to treat. Glutathione has anti-melanogenic and antioxidant properties, which led to its use as a skin-lightening agent. Our objective was to review the published evidence and literature on the efficacy and safety of glutathione as a skin-lightening agent and in the treatment of melasma.

Electric, thermal, and thermoelectric magnetoconductivity for Weyl/multi-Weyl semimetals in planar Hall set-ups induced by the combined effects of topology and strain.

We continue our investigation of the response tensors in planar Hall (or planar thermal Hall) configurations where a three-dimensional Weyl/multi-Weyl semimetal is subjected to the combined influence of an electric field (and/or temperature gradient ) and an effective magnetic field , generalizing the considerations of Phys. Rev. B 108 (2023) 155132 and Physica E 159 (2024) 115914.

Transport properties in non-Fermi liquid phases of nodal-point semimetals.

In this review, we survey the current progress in computing transport properties in semimetals which harbour non-Fermi liquid (NFL) phases. We first discuss the widely-used Kubo formalism, which can be applied to the effective theory describing the stable NFL phase obtained via a renormalization group procedure and, hence, is applicable for temperatures close to zero (e.g.

A Versatile Reversible, Degenerative Chain Transfer Mechanism for the Catalytic Living Ring-Opening Metathesis Polymerization.

Most metathesis polymers based on norbornene derivatives carry a vinyl end group. Here we show that these vinyl end groups readily undergo a degenerative exchange of the terminal methylene unit in the presence of sub-stoichiometric amounts of a propagating metathesis polymer carrying a Grubbs ruthenium complex. We show that this degenerative exchange can be exploited in synthesizing ROMP polymers in a catalytic living fashion.

H-Glass Supported Hybrid Gold Nano-Islands for Visible-Light-Driven Hydrogen Evolution.

Flat panel reactors, coated with photocatalytic materials, offer a sustainable approach for the commercial production of hydrogen (H) with zero carbon footprint. Despite this, achieving high solar-to-hydrogen (STH) conversion efficiency with these reactors is still a significant challenge due to the low utilization efficiency of solar light and rapid charge recombination. Herein, hybrid gold nano-islands (HGNIs) are developed on transparent glass support to improve the STH efficiency.

Direction-dependent conductivity in planar Hall set-ups with tilted Weyl/multi-Weyl semimetals.

We compute the magnetoelectric conductivity tensors in planar Hall set-ups, which are built with tilted Weyl semimetals (WSMs) and multi-Weyl semimetals (mWSMs), considering all possible relative orientations of the electromagnetic fields (and) and the direction of the tilt. The non-Drude part of the response arises from a nonzero Berry curvature in the vicinity of the WSM/mWSM node under consideration. Only in the presence of a nonzero tilt do we find linear-in-|B|terms in set-ups where the tilt-axis is not perpendicular to the plane spanned byand.

VertXNet: an ensemble method for vertebral body segmentation and identification from cervical and lumbar spinal X-rays.

Accurate annotation of vertebral bodies is crucial for automating the analysis of spinal X-ray images. However, manual annotation of these structures is a laborious and costly process due to their complex nature, including small sizes and varying shapes. To address this challenge and expedite the annotation process, we propose an ensemble pipeline called VertXNet.

Understanding the current acute aortic syndrome (AAS) pathways-The Collaborative Acute Aortic Syndrome Project (CAASP) protocol.

Background: Acute aortic syndrome (AAS) is an emergency associated with high peri-hospital mortality rates. Variable clinical presentation makes timely diagnosis challenging and such delays in diagnosis directly impact patient outcomes.

Aims And Objectives: The aims of the Collaborative Acute Aortic Syndrome Project (CAASP) are to characterise and evaluate the current AAS pathways of a cohort of hospitals in the UK, USA and New Zealand to determine if patient outcomes are influenced by the AAS pathway (time to hospital admission, diagnosis and management plan) and demographic, social, geographic and patient-specific factors (clinical presentation and comorbidities).

Formation of Chlorine in the Atmosphere by Reaction of Hypochlorous Acid with Seawater.

The highly reactive dihalogens play a significant role in the oxidative chemistry of the troposphere. One of the main reservoirs of these halogens is hypohalous acids, HOX, which produce dihalogens in the presence of halides (Y), where X, Y = Cl, Br, I. These reactions occur in and on aerosol particles and seawater surfaces and have been studied experimentally and by field observations.

Interventional radiology training in the UK: a view from within-a national survey.

Objective: Interventional radiology (IR) training in the UK has evolved since recognition as a subspecialty in 2010 and introduction of a new curriculum in 2021. The changing landscape, increasing workload and COVID-19 have affected training. The purpose of this study was to review trainees' perspectives on training and develop strategies to further improve training.

Research should remain a priority in 21st century radiology recruitment to training.

Research drives innovation, however, recently Clinical Radiology has been overwhelmed by increased clinical demand, workforce shortages and lack of funding/protected research time. The newly released 2023 radiology speciality application process gives research a lower priority compared to other domains such as audit which is concerning given the current lack of research culture within the speciality. It is vital for the future radiology workforce to engage with research and in order to fulfil the Royal College of Radiologist's new curriculum aims of strengthening research within training, we must continue attracting the brightest and best candidates and ensure research remains a priority.

Scoring Systems to Predict Survival or Neurological Recovery after Out-of-hospital Cardiac Arrest.

Numerous prediction scores have been developed to better inform clinical decision-making following out-of-hospital cardiac arrest (OHCA), however, there is no consensus among clinicians over which score to use. The aim of this review was to identify and compare scoring systems to predict survival and neurological recovery in patients with OHCA. A structured literature search of the MEDLINE database was carried out from inception to December 2021.

Practical Route for Catalytic Ring-Opening Metathesis Polymerization.

Norbornene derivatives are typical monomers for ring-opening metathesis polymerization (ROMP) for synthesizing highly functional polymers. However, the lack of catalytic methods, that is, the lack of readily available chain transfer agents (CTAs) for these monomers has been a significant cost limitation when large-scale syntheses are required. Here, we report commercially available styrene and its derivatives as efficient regioselective CTAs for the catalytic synthesis of metathesis polymers requiring up to 1000 times less ruthenium than in classical ROMP experiments.

Macrochain Transfer Agents for Catalytic Ring-Opening Metathesis Polymerization.

A monosubstituted 1,3-diene derivative attached to a polymer is demonstrated to act as a macrochain transfer agent in catalytic ring-opening metathesis polymerization. PEG- and PLA-based macrochain transfer agents were synthesized in a few steps and were characterized using NMR spectroscopy, size exclusion chromatography (SEC) and matrix-assisted laser desorption/ionization-time-of-flight (MALDI-ToF) mass spectrometry. Poly(l-lactide) based diblock copolymer, poly(ethylene glycol)-based diblock, and triblock (ABA type) copolymers of varied chain lengths were prepared catalytically in a one-pot approach via metathesis polymerization.

Catalytic Living Ring-Opening Metathesis Polymerization Using Vinyl Ethers as Effective Chain-Transfer Agents.

A catalytic living ring-opening metathesis copolymerization (ROMP) method is described that relies on a degenerative, reversible and regioselective exchange of propagating Fischer-carbenes. All characteristics of a living polymerization such as narrow dispersity, excellent molar mass control and the ability to form block copolymers are achieved by this method. The method allows the use of up to 200 times less ruthenium complex than traditional living ROMP.

Chain transfer agents for the catalytic ring opening metathesis polymerization of norbornenes.

Here, we present a detailed study of the metathesis activity of conjugated 1,3 diene derivatives in ring opening metathesis polymerization (ROMP) using Grubbs' 3rd generation catalyst (G3). A comprehensive screening of those derivatives revealed that monosubstituted 1,3 dienes show similar reactivities towards G3-alkylidenes as norbornene derivatives. Therefore, they represent perfect candidates for chain transfer agents in a kinetically controlled catalytic ROMP.

Erratum: Symmetry and Higher-Order Exceptional Points [Phys. Rev. Lett. 127, 186601 (2021)].

This corrects the article DOI: 10.1103/PhysRevLett.127.

Controlled Alternating Metathesis Copolymerization of Terminal Alkynes.

Terminal alkynes display high reactivity toward Ru-carbene metathesis catalysts. However, the formation of a less reactive bulky carbene hinders their homopolymerization. Simultaneously, the higher reactivity of alkynes does not allow efficient cross propagation with sterically less-hindered cycloalkene monomers, resulting in inefficient copolymerization.

Pulsed-Addition ROMP: Catalytic Syntheses of Heterotelechelic Polymers via Regioselective Chain Transfer Agents.

Regioselective chain transfer agents are used to synthesize narrowly dispersed heterotelechelic polymers with a 15-fold decrease in catalyst consumption using the pulsed addition ROMP (PA-ROMP) technique. The commercially available Grubbs' third-generation catalyst (G3) is easily prefunctionalized with chain transfer agents in a short reaction time (30 min). After addition and consumption of a monomer, the excess chain transfer agent in the reaction medium end-functionalizes the polymer chain and regenerates the initiator very quickly (within 10 min) via a ring-opening-ring-closing sequence.

One-Pot Heterotelechelic Metathesis Polymers via Regioselective Chain Transfer Agents.

Single chain transfer agents are used to synthesize narrowly distributed heterotelechelic ROMP polymers in one pot, exploiting a new mechanistic and synthetic approach. The chain transfer agents carrying different functional groups are synthesized in a few straightforward steps. Prefunctionalization of commercially available Grubbs' third-generation catalyst is realized in situ using regioselective chain transfer agents within a short reaction period.

Raman response and shear viscosity in the non-Fermi liquid phase of Luttinger semimetals.

Luttinger semimetals represent materials with strong spin-orbit coupling, harboring doubly-degenerate quadratic band touchings at the Brillouin zone center. In the presence of Coulomb interactions, such a system exhibits a non-Fermi liquid phase [dubbed as the Luttinger-Abrikosov-Beneslavskii (LAB) phase], at low temperatures and zero doping. However, a clear experimental evidence of this emergent state remains elusive to this date.