Search

Temperature-dependent measurements of the pulsed light-current characteristics of InGaN light-emitting diodes that were thermally annealed at different temperatures have been investigated. A distinct light output, at a fixed current density, with operating temperature arises where the light output increases as the operating temperature is reduced from 300 K, reaches a maximum, and then decreases with subsequent reductions of the operating temperature. We observe that light-emitting diodes thermally annealed at higher temperatures, which is believed to increase the number of electrically activated acceptors in the p layers, have a lower light output below 300 K and the maximum light output shifts to higher operating temperatures. Measured absorption and emission spectra show that the thermal anneal process has not affected the structure of the quantum wells within these samples. The light output, for a fixed current density, has been simulated as a function of operating temperature, and we find that by changing the concentration of acceptor atoms, compensating donor atoms, and the hole mobility in the p layers, the trends observed experimentally can be reproduced. On the basis of the simulations we find that the distinct behavior of the light output with operating temperature is due to the combination of Shockley-Reed-Hall recombination, at operating temperatures around 300 K, and electron drift leakage, at operating temperature below 300 K, and the increase of the acceptor concentration results in an increased electron drift leakage due to the change of the concomitant hole mobility. The simulations support the view that the experimental observations can be explained through changes of the acceptor concentration in the p layers when the thermal anneal temperature is increased. [ABSTRACT FROM AUTHOR]

Introduction: Screening for smoking when people interact with healthcare services and referral of those who smoke to stop smoking services (SSSs) is a key component of efforts to tackle tobacco use. However, little is known about what happens after someone is referred or signposted to SSSs., Methods: As part of the Cessation of Smoking Trial in the Emergency Department (NCT04854616), those randomised to intervention (n= 505) were referred to local SSSs (along with receiving brief advice and an e-cigarette starter kit) and those randomised to control (n= 502) were given contact details for the same services (signposted). SSS engagement data was collected: 1) directly from participants and 2) from SSS, additional qualitative data came from 33 participant interviews., Results: Engagement with SSSs was very low. 3.2% (n=16) of those in the intervention group and 2.4% (n=12) in the control group reported attending a one-to-one support session. From SSS data, engagement was also low with 8.9% (n=43) of those referred engaging and 3.1% (n=15) going on to quit with SSS support. The majority of the 24 intervention participants interviewed did not recall being contacted by an SSS., Conclusion: Referral or signposting to stop smoking services within an Emergency Department based trial resulted in very low levels of engagement. Barriers to engagement identified included participants not being contacted by SSSs and the support offered not meeting their needs., Implications: Referral or signposting of those who smoke to Stop smoking services from the Emergency Department resulted in low rates of engagement in this large multi-centre randomised controlled trial. In order to better support those who smoke it may be more effective for smoking cessation advice to be offered 'in the moment' within clinical settings, and follow-up to be proactively offered rather than relying on people being motivated to contact the services themselves or engaging when contacted., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco.)

Background and Aims: Youth use of disposable vapes has increased markedly in the United Kingdom in recent years, yet little is known about the motivations, experiences and perceptions of young people themselves. This study aimed to explore young people's experiences and use of disposable vapes., Methods: This was a qualitative study recruiting young people reporting regularly vaping disposables, collecting data via dyad guided, individual and group interviews. Data analysis was theoretically informed by the Social Ecological Model. Inductive and deductive coding approaches were used, with resolution of coded interpretations by consensus., Results: Twenty-nine young people aged 16-20 years participated in qualitative interviews. At the individual level, participants discussed how characteristics of disposable vapes were important to them-particularly price, accessibility and the attractive designs, colours, names and flavours. Young people frequently engaged in both vaping and tobacco smoking, seeing the behaviours as interchangeable dependent on context, and having inaccurate relative harm perceptions of vaping compared with smoking. Experimentation was widespread and many used vapes as a way of managing stress and anxiety. Vaping was positioned as a social behaviour, common among peers. Parental influence on vaping behaviour was minimal, although vaping initiation could be influenced by family vaping norms. Culturally, vaping was a widespread normalized behaviour. Young people were aware of media reports and potential harms, but were less aware of smoking related harms as a consequence., Conclusions: Disposable vapes appear to be attractive and accessible to young people in the United Kingdom. Vaping is normalized in this population, despite being seen as potentially damaging to health, and vaping and smoking are engaged in interchangeably. Underage sales of vapes are reportedly widespread. Strict regulation, such as banning products or increasing prices, may prompt UK youth to switch from vaping to smoking., (© 2024 The Author(s). Addiction published by John Wiley & Sons Ltd on behalf of Society for the Study of Addiction.)

Background: Supporting people to quit smoking is one of the most powerful interventions to improve health. The Emergency Department (ED) represents a potentially valuable opportunity to deliver a smoking cessation intervention if it is sufficiently resourced. The objective of this trial was to determine whether an opportunistic ED-based smoking cessation intervention can help people to quit smoking., Methods: In this multicentre, parallel-group, randomised controlled superiority trial conducted between January and August 2022, adults who smoked daily and attended one of six UK EDs were randomised to intervention (brief advice, e-cigarette starter kit and referral to stop smoking services) or control (written information on stop smoking services). The primary outcome was biochemically validated abstinence at 6 months., Results: An intention-to-treat analysis included 972 of 1443 people screened for inclusion (484 in the intervention group, 488 in the control group). Of 975 participants randomised, 3 were subsequently excluded, 17 withdrew and 287 were lost to follow-up. The 6-month biochemically-verified abstinence rate was 7.2% in the intervention group and 4.1% in the control group (relative risk 1.76; 95% CI 1.03 to 3.01; p=0.038). Self-reported 7-day abstinence at 6 months was 23.3% in the intervention group and 12.9% in the control group (relative risk 1.80; 95% CI 1.36 to 2.38; p<0.001). No serious adverse events related to taking part in the trial were reported., Conclusions: An opportunistic smoking cessation intervention comprising brief advice, an e-cigarette starter kit and referral to stop smoking services is effective for sustained smoking abstinence with few reported adverse events., Trial Registration Number: NCT04854616., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY. Published by BMJ.)

Helicobacter pylori ( H. pylori) infection is a known cause of many digestive diseases, including gastritis, peptic ulcers, and gastric cancer. However, the underlying mechanisms by which H. pylori infection triggers these disorders are still not clearly understood. Gastric cancer is a slow progressing disease, which makes it difficult to study. We have developed an accelerated disease progression mouse model, which leverages mice deficient in the myeloid differentiation primary response 88 gene ( Myd88 -/- ) infected with Helicobacter felis ). Using this model and gastric biopsy samples from patients, we report that activation of the Toll/interleukin-1 receptor (TIR)-domain-containing adaptor inducing interferon-β (TRIF)-type I interferon (IFN-I) signaling pathway promotes H. felis ). Using this model and gastric biopsy samples from patients, we report that activation of the Toll/interleukin-1 receptor (TIR)-domain-containing adaptor inducing interferon-β (TRIF)-type I interferon (IFN-I) signaling pathway promotes Helicobacter -induced disease progression toward severe gastric pathology and gastric cancer development. Further, results implicated downstream targets of this pathway in disease pathogenesis. These findings may facilitate stratification of Helicobacter -infected patients and thus enable treatment prioritization of patients., Competing Interests: All authors declare that no conflict of interest exists., (© 2024 The Authors.)

Objectives: The Cessation of Smoking Trial in the Emergency Department (COSTED) trial aims to ascertain whether brief advice, the provision of an e-cigarette starter kit and referral to stop smoking services (SSS), increases smoking cessation in people attending the emergency department. Patient and public involvement (PPI) and scoping work were undertaken to select an appropriate e-cigarette for the trial., Design and Setting: PPI consultation and feasibility scoping about potential devices with a professional and lay panel, all based in England. Consultation was via email, telephone or video interview. This work took place between April and July 2021, prior to recruitment commencing for the COSTED trial., Participants: A professional panel (n=7) including representatives from academia, SSS and the independent vaping industry, and a PPI lay panel (n=3) who smoke or vape., Results: The professional panel recommended a shortlist of devices which were tested by the PPI lay panel. Key criteria for selecting an appropriate e-cigarette for smoking cessation intervention include satisfaction, usability, affordability and availability. Simplicity of use was highlighted by the PPI lay panel, who found refillable devices complex, and availability of consumables was highlighted as more important than price by both panels. The pod device selected for inclusion was rated highly for satisfaction and usability and had mid-price range and consumables which were widely available., Conclusions: To select the most appropriate device for the COSTED trial, each criterion required assessment to ensure the best fit to the intervention context and needs of the target population. There is a need for guidance to help enable decision-making about choice of vape products, tailored to service users' needs. We propose a bespoke checklist template, based on our findings, to assist with this process. This has applicability to the recent government announcement of a 'Swap to Stop' programme, offering a vaping starter kit to smokers across England, allowing services flexibility to shape their own programmes and models of delivery., Trial Registration Number: Clinical trial number NCT04854616; pre-results., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Introduction: Biochemical verification of smoking status prior to recruitment into smoking cessation trials is widely used to confirm smoking status, most commonly using exhaled carbon monoxide (CO). There is variation in the level of CO used as a biochemical inclusion criterion, and thus the possibility for people reporting to be current smokers to be incorrectly excluded from trials., Methods: As part of the Cessation of Smoking Trial in the Emergency Department, people attending the Emergency Department (ED) who reported being current daily smokers underwent CO testing to confirm eligibility. Elective semi-structured interviews were undertaken with the researchers who recruited participants. As part of the interviews, researchers were asked their views and experiences with CO testing., Results: Of the 1320 participants who reported being current daily smokers and underwent CO testing, 300 (22.7%) blew a CO reading of 7 ppm or less and were excluded from taking part. Possible explanations offered by researchers for participants blowing low CO readings were (1) long wait times in the ED, therefore a long period having elapsed since people had last smoked and (2) patients having reduced smoking for the period before the ED attendance due to ill health., Conclusions: Biochemical verification has the potential to improve internal validity of smoking cessation for inclusion in trials, but at the cost of reduced generalisability through exclusion of participants who would receive the intervention if it were implemented in practice. We would recommend researchers carefully consider whether it is appropriate and necessary to include biochemical verification as an inclusion criterion., Competing Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2023.)

Rationale: Offering a primary care service that can provide good quality primary care at emergency departments may reduce pressure on usual emergency department (ED) services., Aims and Objectives: To evaluate the acceptability, satisfaction, and potential impacts of a co-located primary care service at an emergency department., Methods: This is a prospective feasibility study and service evaluation comprising a narrative summary of activity, satisfaction, well-being, and safety, and comparisons of wait times for ED services by patient category ('minor', 'majors', 'paediatric' or 'resus') before and during the service operation. Patients and staff were asked using semistructured interview topic guides about service perception, well-being, representation within 48 h, safety concerns, and/or satisfaction. Wait times for patient categories in usual ED care service were in secondary care electronic records. Pathway changes were captured under primary care electronic records., Results: Approximately 96% of general practitioner streaming and treatment (GPST) patients were seen within 1 h. There was a statistically significant reduction in ED patients with minor injuries or illnesses waiting >4 h for admission or discharge 'breaches' during the 3 months that GPST was operating compared with the previous 3 months (p ≤ 0.005). Wait times for other ED services did not significantly improve. A total of 769 walk-in patients received GPST consultation and 661 (86%) needed no further ED intervention. Fast discharge was a major determinant of patient satisfaction. No staff expressed dissatisfaction, but some suggested possible improvements in eligibility criteria and built environment design features., Conclusion: Provision of GPST correlated with shorter waits for discharge from ED. Patient and staff experiences of GPST were positive., (© 2022 The Authors. Journal of Evaluation in Clinical Practice published by John Wiley & Sons Ltd.)

Correlative light-electron microscopy (CLEM) requires the availability of robust probes which are visible both in light and electron microscopy. Here we demonstrate a CLEM approach using small gold nanoparticles as a single probe. Individual gold nanoparticles bound to the epidermal growth factor protein were located with nanometric precision background-free in human cancer cells by light microscopy using resonant four-wave mixing (FWM), and were correlatively mapped with high accuracy to the corresponding transmission electron microscopy images. We used nanoparticles of 10 nm and 5 nm radius, and show a correlation accuracy below 60 nm over an area larger than 10 µm size, without the need for additional fiducial markers. Correlation accuracy was improved to below 40 nm by reducing systematic errors, while the localisation precision is below 10 nm. Polarisation-resolved FWM correlates with nanoparticle shapes, promising for multiplexing by shape recognition in future applications. Owing to the photostability of gold nanoparticles and the applicability of FWM microscopy to living cells, FWM-CLEM opens up a powerful alternative to fluorescence-based methods., (© 2023. The Author(s).)

Introduction: Attendees of emergency departments (EDs) have a higher than expected prevalence of smoking. ED attendance may be a good opportunity to prompt positive behaviour change, even for smokers not currently motivated to quit. This study aims to determine whether an opportunist smoking cessation intervention delivered in the ED can help daily smokers attending the ED quit smoking and is cost-effective., Methods and Analysis: A two-arm pragmatic, multicentred, parallel-group, individually randomised, controlled superiority trial with an internal pilot, economic evaluation and mixed methods process evaluation. The trial will compare ED-based brief smoking cessation advice, including provision of an e-cigarette and referral to local stop smoking services (intervention) with the provision of contact details for local stop smoking services (control). Target sample size is 972, recruiting across 6 National Health Service EDs in England and Scotland. Outcomes will be collected at 1, 3 and 6 months. The primary outcome at 6 months is carbon monoxide verified continuous smoking abstinence., Ethics and Dissemination: The trial was approved by the South Central-Oxford B Research Committee (21/SC/0288). Dissemination will include the publication of outcomes, and the process and economic evaluations in peer-reviewed journals. The findings will also be appropriately disseminated to relevant practice, policy and patient representative groups., Trial Registration Number: NCT04854616; protocol V.4.2., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY. Published by BMJ.)

Exposure of mouse oocytes to saturated fatty acids (FAs) such as palmitic acid (PA) has been shown to increase lipid content and cause an endoplasmic reticulum (ER) stress response and changes in the mitochondrial redox state. PA can also disrupt Ca2+ stores in other cell types. The links between these intracellular changes, or whether they are prevented by mono-unsaturated FAs such as oleic acid (OA), is unclear. Here, we have investigated the effects of FAs on mouse oocytes, that are maturated in vitro, using coherent anti-Stokes Raman scattering and two-photon fluorescence microscopy. When oocytes were matured in the presence of PA, there were changes in the aggregation pattern and size of lipid droplets that were mitigated by co-incubation in OA. Maturation in PA alone also caused a distinctive disruption of the ER structure. This effect was prevented by incubation of OA with PA. In contrast, maturation of mouse oocytes in medium containing PA was not associated with any significant change in the redox state of mitochondria or the Ca2+ content of intracellular stores. These data suggest that a primary effect of saturated FAs such as PA on oocytes is to disrupt the structure of the ER and this is not due to an effect on the mitochondria or Ca2+ stores.

Coherent anti-Stokes Raman scattering (CARS) implemented as a vibrational micro-spectroscopy modality eradicates the need for potentially perturbative fluorescent labeling while still providing high-resolution, chemically specific images of biological samples. Isotopic substitution of hydrogen atoms with deuterium introduces minimal change to molecular structures and can be coupled with CARS microscopy to increase chemical contrast. Here, we investigate HeLa cells incubated with non-deuterated or deuterium-labeled fatty acids, using an in-house-developed hyperspectral CARS microscope coupled with an unsupervised quantitative data analysis algorithm, to retrieve Raman susceptibility spectra and concentration maps of chemical components in physically meaningful units. We demonstrate that our unsupervised analysis retrieves the susceptibility spectra of the specific fatty acids, both deuterated and non-deuterated, in good agreement with reference Raman spectra measured in pure lipids. Our analysis, using the cell-silent spectral region, achieved excellent chemical specificity despite having no prior knowledge and considering the complex intracellular environment inside cells. The quantitative capabilities of the analysis allowed us to measure the concentration of deuterated and non-deuterated fatty acids stored within cytosolic lipid droplets over a 24 h period. Finally, we explored the potential use of deuterium-labeled lipid droplets for non-invasive cell tracking, demonstrating an effective application of the technique for distinguishing between cells in a mixed population over a 16 h period. These results further demonstrate the chemically specific capabilities of hyperspectral CARS microscopy to characterize and distinguish specific lipid types inside cells using an unbiased quantitative data analysis methodology.