Effect of fluoridated water on invasive NHS dental treatments for adults: the LOTUS retrospective cohort study and economic evaluation.

Background: Most water fluoridation studies were conducted on children before the widespread introduction of fluoride toothpastes. There is a lack of evidence that can be applied to contemporary populations, particularly adolescents and adults. Objective: To pragmatically assess the clinical and cost effectiveness of water fluoridation for preventing dental treatment and improving oral health in a contemporary population of adults, using a natural experiment design. Design: Retrospective cohort study using routinely collected National Health Service dental claims (FP17) data. Setting: National Health Service primary dental care: general dental practices, prisons, community dental services, domiciliary settings, urgent/out-of-hours and specialised referral-only services. Participants: Dental patients aged 12 years and over living in England (n = 6,370,280). Intervention and comparison: Individuals exposed to drinking water with a fluoride concentration ≥ 0.7 mg F/l between 2010 and 2020 were matched to non-exposed individuals on key characteristics using propensity scores. Outcome measures: Primary: number of National Health Service invasive dental treatments (restorations/'fillings' and extractions) received per person between 2010 and 2020. Secondary: decayed, missing and filled teeth, missing teeth, inequalities, cost effectiveness and return on investment. Data sources: National Health Service Business Services Authority dental claims data. Water quality monitoring data. Primary outcome: Predicted mean number of invasive dental treatments was 3% lower in the optimally fluoridated group than in the sub/non-optimally fluoridated group (incidence rate ratio 0.969, 95% CI 0.967 to 0.971), a difference of -0.173 invasive dental treatments (95% CI -0.185 to -0.161). This magnitude of effect is smaller than what most stakeholders we engaged with (n = 50/54) considered meaningful. Secondary outcomes: Mean decayed, missing and filled teeth were 2% lower in the optimally fluoridated group, with a difference of -0.212 decayed, missing and filled teeth (95% CI -0.229 to -0.194). There was no statistically significant difference in the mean number of missing teeth per person (0.006, 95% CI -0.008 to 0.021). There was no compelling evidence that water fluoridation reduced social inequalities in treatments received or missing teeth; however, decayed, missing and filled teeth data did not demonstrate a typical inequalities gradient. Optimal water fluoridation in England in 2010-20 was estimated to cost £10.30 per person (excluding original setup costs). Mean National Health Service treatment costs for fluoridated patients 2010-20 were 5.5% lower per person, by £22.26 (95% CI -£23.09 to -£21.43), and patients paid £7.64 less in National Health Service dental charges per person (2020 prices). Limitations: Pragmatic, observational study with potential for non-differential errors of misclassification in fluoridation assignment and outcome measurement and residual and/or unmeasured confounding. Decayed, missing and filled teeth data have not been validated. Water fluoridation cost estimates are based on existing programmes between 2010 and 2020, and therefore do not include the potentially significant capital investment required for new programmes. Conclusions: Receipt of optimal water fluoridation between 2010 and 2020 resulted in very small health effects, which may not be meaningful for individuals, and we could find no evidence of a reduction in social inequalities. Existing water fluoridation programmes in England produced a positive return on investment between 2010 and 2020 due to slightly lower National Health Service treatment costs. These relatively small savings should be evaluated against the projected costs and lifespan of any proposed capital investment in water fluoridation, including new programmes. Future work: National Health Service dental data are a valuable resource for research. Further validation and measures to improve quality and completeness are warranted. Trial registrations: This trial is registered as ISRCTN96479279, CAG: 20/CAG/0072, IRAS: 20/NE/0144. Funding: This award was funded by the National Institute for Health and Care Research (NIHR) Public Health Research programme (NIHR award ref: NIHR128533) and is published in full in Public Health Research; Vol. 12, No. 5. See the NIHR Funding and Awards website for further award information.

Fluoride is a natural mineral that prevents tooth decay. It is added to some drinking water and toothpastes to improve dental health. Water with fluoride added is known as 'optimally fluoridated'. Most research on water fluoridation was carried out before fluoride was added to toothpastes in the 1970s and only included children. We wanted to know if water fluoridation still produced large reductions in tooth decay, now that decay levels are much lower because of fluoride in toothpaste. We also wanted to look at its effect on adults and teenagers. Dental patients we spoke to told us they worried about needing treatment with the 'drill', or 'injection', losing their teeth and paying for their dental care. To see if water fluoridation helped with these concerns, we compared the National Health Service dental records of 6.4 million adults and teenagers who received optimally fluoridated or non-optimally fluoridated water in England between 2010 and 2020. We found water fluoridation made a very small difference to each person. Between 2010 and 2020, the number of NHS fillings and extractions was 3% lower per person for those who received optimally fluoridated water. We found no difference in the number of teeth lost per person and no strong sign that fluoridation reduced differences in dental health between rich and poor areas. Between 2010 and 2020, the cost of optimal water fluoridation was £10.30 per person (not including setup costs). National Health Service dental patients who received optimally fluoridated water cost the National Health Service £22.26 (5.5%) less and paid £7.64 (2%) less per person in National Health Service dental charges over the 10 years. The benefits we found are much smaller than in the past, when toothpastes did not contain fluoride. The cost to set up a new water fluoridation programme can be high. Communities may need to consider if these smaller benefits would still outweigh the costs.

Association between regulator inspection and ratings on primary care prescribing: an observational study in England 2014 to 2019.

BACKGROUND: Healthcare regulators in many countries undertake inspections of healthcare providers and publish inspection outcomes with the intention of improving quality of care. Comprehensive inspections of general practices in England by the Care Quality Commission began for the first time in 2014. It is assumed that inspection and rating will raise standards and improve care, but the presence and extent of any improvements is unknown. We aim to determine if practice inspection ratings are associated with past performance on prescribing indicators and if prescribing behaviour changes following inspection. METHODS: Longitudinal study using a dataset of 6771 general practices in England. Practice inspection date and score was linked with monthly practice-level data on prescribing indicators relating to antibiotics, hypnotics and non-steroidal anti-inflammatory drugs. The sample covers practices receiving their first inspection between September 2014 and December 2018. Regression analysis and the differential timing of inspections is used to identify the impact on prescribing. RESULTS: Better-rated practices had better prescribing in the period before inspections began. In the six months following inspections, no overall change in prescribing was observed. However, the differences between the best and worse rated practices were reduced but not fully. The same is also true when taking a longer-term view. There is little evidence that practices responded in anticipation of inspection or reacted differently once the ratings were made public. CONCLUSION: While some of the observed historic variation in prescribing behaviour has been lessened by the process of inspection and ratings, we find this change is small and appears to come from both improvements among lower-rated practices and deteriorations among higher-rated practices. While inspection and rating no doubt had other impacts, these prescribing indicators were largely unchanged.

Locum doctor working and quality and safety: a qualitative study in English primary and secondary care.

BACKGROUND: The use of temporary doctors, known as locums, has been common practice for managing staffing shortages and maintaining service delivery internationally. However, there has been little empirical research on the implications of locum working for quality and safety. This study aimed to investigate the implications of locum working for quality and safety. METHODS: Qualitative semi-structured interviews and focus groups were conducted with 130 participants, including locums, patients, permanently employed doctors, nurses and other healthcare professionals with governance and recruitment responsibilities for locums across primary and secondary healthcare organisations in the English NHS. Data were collected between March 2021 and April 2022. Data were analysed using reflexive thematic analysis and abductive analysis. RESULTS: Participants described the implications of locum working for quality and safety across five themes: (1) 'familiarity' with an organisation and its patients and staff was essential to delivering safe care; (2) 'balance and stability' of services reliant on locums were seen as at risk of destabilisation and lacking leadership for quality improvement; (3) 'discrimination and exclusion' experienced by locums had negative implications for morale, retention and patient outcomes; (4) 'defensive practice' by locums as a result of perceptions of increased vulnerability and decreased support; (5) clinical governance arrangements, which often did not adequately cover locum doctors. CONCLUSION: Locum working and how locums were integrated into organisations posed some significant challenges and opportunities for patient safety and quality of care. Organisations should take stock of how they work with the locum workforce to improve not only quality and safety but also locum experience and retention.

Comparing the clinical practice and prescribing safety of locum and permanent doctors: observational study of primary care consultations in England.

BACKGROUND: Temporary doctors, known as locums, are a key component of the medical workforce in the NHS but evidence on differences in quality and safety between locum and permanent doctors is limited. We aimed to examine differences in the clinical practice, and prescribing safety for locum and permanent doctors working in primary care in England. METHODS: We accessed electronic health care records (EHRs) for 3.5 million patients from the CPRD GOLD database with linkage to Hospital Episode Statistics from 1st April 2010 to 31st March 2022. We used multi-level mixed effects logistic regression to compare consultations with locum and permanent GPs for several patient outcomes including general practice revisits; prescribing of antibiotics; strong opioids; hypnotics; A&E visits; emergency hospital admissions; admissions for ambulatory care sensitive conditions; test ordering; referrals; and prescribing safety indicators while controlling for patient and practice characteristics. RESULTS: Consultations with locum GPs were 22% more likely to involve a prescription for an antibiotic (OR = 1.22 (1.21 to 1.22)), 8% more likely to involve a prescription for a strong opioid (OR = 1.08 (1.06 to 1.09)), 4% more likely to be followed by an A&E visit on the same day (OR = 1.04 (1.01 to 1.08)) and 5% more likely to be followed by an A&E visit within 1 to 7 days (OR = 1.05 (1.02 to 1.08)). Consultations with a locum were 12% less likely to lead to a practice revisit within 7 days (OR = 0.88 (0.87 to 0.88)), 4% less likely to involve a prescription for a hypnotic (OR = 0.96 (0.94 to 0.98)), 15% less likely to involve a referral (OR = 0.85 (0.84 to 0.86)) and 19% less likely to involve a test (OR = 0.81 (0.80 to 0.82)). We found no evidence that emergency admissions, ACSC admissions and eight out of the eleven prescribing safety indicators were different if patients were seen by a locum or a permanent GP. CONCLUSIONS: Despite existing concerns, the clinical practice and performance of locum GPs did not appear to be systematically different from that of permanent GPs. The practice and performance of both locum and permanent GPs is likely shaped by the organisational setting and systems within which they work.

How effective and cost-effective is water fluoridation for adults and adolescents? The LOTUS 10-year retrospective cohort study.

OBJECTIVE: To pragmatically assess the clinical and cost-effectiveness of water fluoridation for preventing dental treatment and improving oral health in a contemporary population of adults and adolescents, using a natural experiment design. METHODS: A 10-year retrospective cohort study (2010-2020) using routinely collected NHS dental treatment claims data. Participants were patients aged 12 years and over, attending NHS primary dental care services in England (17.8 million patients). Using recorded residential locations, individuals exposed to drinking water with an optimal fluoride concentration (≥0.7 mg F/L) were matched to non-exposed individuals using propensity scores. Number of NHS invasive dental treatments, DMFT and missing teeth were compared between groups using negative binomial regression. Total NHS dental treatment costs and cost per invasive dental treatment avoided were calculated. RESULTS: Matching resulted in an analytical sample of 6.4 million patients. Predicted mean number of invasive NHS dental treatments (restorations 'fillings'/extractions) was 3% lower in the optimally fluoridated group (5.4) than the non-optimally fluoridated group (5.6) (IRR 0.969, 95% CI 0.967, 0.971). Predicted mean DMFT was 2% lower in the optimally fluoridated group (IRR 0.984, 95% CI 0.983, 0.985). There was no difference in the predicted mean number of missing teeth per person (IRR 1.001, 95% CI 0.999, 1.003) and no compelling evidence that water fluoridation reduced social inequalities in dental health. Optimal water fluoridation in England 2010-2020 was estimated to cost £10.30 per person (excludes initial set-up costs). NHS dental treatment costs for optimally fluoridated patients 2010-2020 were 5.5% lower, by £22.26 per person (95% CI -£21.43, -£23.09). CONCLUSIONS: Receipt of optimal water fluoridation 2010-2020 resulted in very small positive health effects which may not be meaningful for individuals. Existing fluoridation programmes in England produced a positive return on investment between 2010 and 2020 due to slightly lower NHS dental care utilization. This return should be evaluated against the projected costs and lifespan of any proposed capital investment in water fluoridation, including new programmes.

Pathways toward commercial perovskite/silicon tandem photovoltaics.

Perovskite/silicon tandem solar cells offer a promising route to increase the power conversion efficiency of crystalline silicon (c-Si) solar cells beyond the theoretical single-junction limitations at an affordable cost. In the past decade, progress has been made toward the fabrication of highly efficient laboratory-scale tandems through a range of vacuum- and solution-based perovskite processing technologies onto various types of c-Si bottom cells. However, to become a commercial reality, the transition from laboratory to industrial fabrication will require appropriate, scalable input materials and manufacturing processes. In addition, perovskite/silicon tandem research needs to increasingly focus on stability, reliability, throughput of cell production and characterization, cell-to-module integration, and accurate field-performance prediction and evaluation. This Review discusses these aspects in view of contemporary solar cell manufacturing, offers insights into the possible pathways toward commercial perovskite/silicon tandem photovoltaics, and highlights research opportunities to realize this goal.

Sublimed C60 for efficient and repeatable perovskite-based solar cells.

Thermally evaporated C60 is a near-ubiquitous electron transport layer in state-of-the-art p-i-n perovskite-based solar cells. As perovskite photovoltaic technologies are moving toward industrialization, batch-to-batch reproducibility of device performances becomes crucial. Here, we show that commercial as-received (99.75% pure) C60 source materials may coalesce during repeated thermal evaporation processes, jeopardizing such reproducibility. We find that the coalescence is due to oxygen present in the initial source powder and leads to the formation of deep states within the perovskite bandgap, resulting in a systematic decrease in solar cell performance. However, further purification (through sublimation) of the C60 to 99.95% before evaporation is found to hinder coalescence, with the associated solar cell performances being fully reproducible after repeated processing. We verify the universality of this behavior on perovskite/silicon tandem solar cells by demonstrating their open-circuit voltages and fill factors to remain at 1950 mV and 81% respectively, over eight repeated processes using the same sublimed C60 source material. Notably, one of these cells achieved a certified power conversion efficiency of 30.9%. These findings provide insights crucial for the advancement of perovskite photovoltaic technologies towards scaled production with high process yield.

Sign language delays in deaf 3- to 5-year-olds with deaf parents.

Research has demonstrated that deaf children of deaf signing parents (DOD) are afforded developmental advantages. This can be misconstrued as indicating that no DOD children exhibit early language delays (ELDs) because of their early access to a visual language. Little research has studied this presumption. In this study, we examine 174 ratings of DOD 3- to 5-year-old children, for whom signing in the home was indicated, using archival data from the online database of the Visual Communication and Sign Language Checklist. Our goals were to (1) examine the incidence of ELDs in a cohort of DOD children; (2) compare alternative scaling strategies for identifying ELD children; (3) explore patterns among behavioral ratings with a view toward developing a greater understanding of the types of language behaviors that may lie at the root of language delays; and (4) suggest recommendations for parents and professionals working with language-delayed DOD children. The results indicated that a significant number of ratings suggested ELDs, with a subset significantly delayed. These children likely require further evaluation. Among the less delayed group, ASL skills, rather than communication or cognition, were seen as the major concern, suggesting that even DOD children may require support developing linguistically accurate ASL. Overall, these findings support the need for early and ongoing evaluation of visual language skills in young DOD children.

Characterization of a Putative New Member of the Genus Potyvirus from Kudzu (Pueraria montana var. lobata) in Mississippi.

Kudzu (Pueraria montana var. lobata), a plant native to Southeastern Asia, has become a major noxious weed covering millions of hectares in the Southern United States. A kudzu patch displaying virus-like symptoms located in Ackerman, northeastern Mississippi (MS), was used as a source for virus isolation and characterization involving mechanical and vector transmission, ultrastructural observation, surveys, Sanger and high-throughput genome sequencing, and sequence analyses. The results revealed the presence of a new potyvirus in infected kudzu, closely related to wisteria vein mosaic virus (WVMV) and provisionally named kudzu chlorotic ring blotch virus (KudCRBV). Genome features and pairwise comparison with six WVMV genomes currently available in GenBank and three additional isolates from MS sequenced in this work suggest that KudCRBV is likely a member of a new species in the genus Potyvirus. Furthermore, under experimental conditions, KudCRBV was successfully transmitted by cotton and potato aphids and mechanically to soybean and beans. A state-wide survey revealed several kudzu patches infected by the virus in northern MS.

Efficient and reliable encapsulation for perovskite/silicon tandem solar modules.

Perovskite/silicon tandem solar cells have a tremendous potential to boost renewable electricity production thanks to their very high performance combined with promising cost structure. However, for actual field deployment, any solar cell technology needs to be assembled into modules, where the associated processes involve several challenges that may affect both the performance and stability of the devices. For instance, due to its hygroscopic nature, ethylene vinyl acetate (EVA) is incompatible with perovskite-based photovoltaics. To circumvent this issue, we investigate here two alternative encapsulant polymers for the packaging of perovskite/silicon tandems into minimodules: a thermoplastic polyurethane (TPU) and a thermoplastic polyolefin (TPO) elastomer. To gauge their impact on tandem-module performance and stability, we performed two internationally established accelerated module stability tests (IEC 61215): damp heat exposure and thermal cycling. Finally, to better understand the thermomechanical properties of the two encapsulants and gain insight into their relation to the thermal cycling of encapsulated tandems, we performed a dynamic mechanical thermal analysis. Our understanding of the packaging process of the tandem module provides useful insights for the development of commercially viable perovskite photovoltaics.

Enhanced optoelectronic coupling for perovskite/silicon tandem solar cells.

Monolithic perovskite/silicon tandem solar cells are of great appeal as they promise high power conversion efficiencies (PCEs) at affordable cost. In state-of-the-art tandems, the perovskite top cell is electrically coupled to a silicon heterojunction bottom cell by means of a self-assembled monolayer (SAM), anchored on a transparent conductive oxide (TCO), which enables efficient charge transfer between the subcells1-3. Yet reproducible, high-performance tandem solar cells require energetically homogeneous SAM coverage, which remains challenging, especially on textured silicon bottom cells. Here, we resolve this issue by using ultrathin (5-nm) amorphous indium zinc oxide (IZO) as the interconnecting TCO, exploiting its high surface-potential homogeneity resulting from the absence of crystal grains and higher density of SAM anchoring sites when compared with commonly used crystalline TCOs. Combined with optical enhancements through equally thin IZO rear electrodes and improved front contact stacks, an independently certified PCE of 32.5% was obtained, which ranks among the highest for perovskite/silicon tandems. Our ultrathin transparent contact approach reduces indium consumption by approximately 80%, which is of importance to sustainable photovoltaics manufacturing4.

Discovery and Analyses of Caulimovirid-like Sequences in Upland Cotton (Gossypium hirsutum).

Analyses of Illumina-based high-throughput sequencing data generated during characterization of the cotton leafroll dwarf virus population in Mississippi (2020-2022) consistently yielded contigs varying in size (most frequently from 4 to 7 kb) with identical nucleotide content and sharing similarities with reverse transcriptases (RTases) encoded by extant plant pararetroviruses (family Caulimoviridiae). Initial data prompted an in-depth study involving molecular and bioinformatic approaches to characterize the nature and origins of these caulimovirid-like sequences. As a result, here, we report on endogenous viral elements (EVEs) related to extant members of the family Caulimoviridae, integrated into a genome of upland cotton (Gossypium hirsutum), for which we propose the provisional name "endogenous cotton pararetroviral elements" (eCPRVE). Our investigations pinpointed a ~15 kbp-long locus on the A04 chromosome consisting of head-to-head orientated tandem copies located on positive- and negative-sense DNA strands (eCPRVE+ and eCPRVE-). Sequences of the eCPRVE+ comprised nearly complete and slightly decayed genome information, including ORFs coding for the viral movement protein (MP), coat protein (CP), RTase, and transactivator/viroplasm protein (TA). Phylogenetic analyses of major viral proteins suggest that the eCPRVE+ may have been initially derived from a genome of a cognate virus belonging to a putative new genus within the family. Unexpectedly, an identical 15 kb-long locus composed of two eCPRVE copies was also detected in a newly recognized species G. ekmanianum, shedding some light on the relatively recent evolution within the cotton family.

The use of locum doctors in the NHS - results of a national survey of NHS Trusts in England.

BACKGROUND: Locum working in healthcare organisations has benefits for individual doctors and organisations but there are concerns about the impact of locum working on continuity of care, patient safety, team function and cost. We conducted a national survey of NHS Trusts in England to explore locum work, and better understand why and where locum doctors were needed; how locum doctors were engaged, supported, perceived and managed; and any changes being made in the way locums are used. METHODS: An online survey was sent to 191 NHS Trusts and 98 were returned (51%) including 66 (67%) acute hospitals, 26 (27%) mental health and six (6%) community health providers. Data was analysed using frequency tables, t-tests and correlations. Free-text responses were analysed using thematic analysis. RESULTS: Most NHS Trusts use locums frequently and for varying lengths of time. Trusts prefer to use locums from internal locum banks but frequently rely on locum agencies. The benefits of using locums included maintaining workforce capacity and flexibility. Importantly, care provided by locums was generally viewed as the same or somewhat worse when compared to care provided by permanent doctors. The main disadvantages of using locum agencies included cost, lack of familiarity and impact on organisational development. Some respondents felt that locums could be unreliable and less likely to be invested in quality improvement. NHS Trusts were broadly unfamiliar with the national guidance from NHS England for supporting locums and there was a focus on processes like compliance checks and induction, with less focus on providing feedback and support for appraisal. CONCLUSIONS: Locum doctors provide a necessary service within NHS Trusts to maintain workforce capacity and provide patient care. There are potential issues related to the way that locums are perceived, utilised, and supported which might impact the quality of the care that they provide. Future research should consider the arrangements for locum working and the performance of locums and permanent doctors, investigating the organisation of locums in order to achieve safe and high-quality care for patients.

Locum doctors in English general practices: evidence from a national survey.

BACKGROUND: Locum doctors give practices flexibility to deliver patient services but there are concerns about the impact of locum working on continuity of care, patient safety, team function, and cost. AIM: To explore locum working in English general practices, and understand why and where locum doctors were needed and how they were engaged, supported, perceived, and managed. DESIGN AND SETTING: An online survey was sent to 3745 practices. METHOD: Quantitative responses were analysed using frequency tables, t-tests, and correlations. Free-text responses were analysed using thematic analysis. RESULTS: In total, 605 (16.2%) responses were returned between June and December 2021. Practices made frequent use of locums, preferring regular locums familiar with processes and patients. Disadvantages of agency locums included cost, lack of patient familiarity, and impact on continuity of care. Care provided by locums was generally viewed as the same but sometimes worse compared with permanent GPs. Some practices reported that locums did not always perform the full range of duties, resulting in increased workload for other staff. Practices were largely unfamiliar with national guidance for organisations engaging locums, and, although processes such as verifying documentation were conducted, far fewer responders reported providing feedback, support for revalidation, or professional development. CONCLUSION: Locum working is an essential part of English general practice, but this research raises some concerns about the robustness of arrangements for locum working and the impact on quality and safety of care. Further research is needed about the clinical practice and performance of locums, and to explore how locum working can be organised in ways that assure safe and high-quality care.

Writing knowledge, practices, efficacy, interests, attitudes, and beliefs of deaf education teachers: a randomized controlled trial.

Writing teachers play an extraordinarily important role in their students' writing development. Teachers' motivational beliefs, such as attitudes toward writing, perceptions of their efficacy to teach writing, or preparation to use evidence-based instructional practices, impact their writing instruction, which directly affects the advancement of students' writing skills. Deaf writers are a subpopulation of writers who may face discriminatory beliefs toward their writing development stemming from ableism, audism, or linguicism. Deaf education teachers may doubt their abilities to teach bilingual/multilingual students or teach deaf students experiencing language deprivation. The current study investigates whether deaf education teachers' beliefs can be fostered through an intensive one-year professional development (PD) program designed specifically for deaf education teachers. In this randomized controlled trial, we examine the extent to which the participation of deaf education teachers in specialized PD and subsequent writing instruction implementation (n = 26) impacts their pedagogical content knowledge, use of evidence-based practices for teaching writing, interest, attitudes, efficacy in teaching writing, and epistemological beliefs about writing compared to teachers in a business as usual condition (n = 24). Pre-post regression analyses indicate statistically significant group differences (with the treatment group scoring higher) on all variables except attitude and some epistemological beliefs. We speculate that specialized, sustained PD paired with supported implementation of writing instruction and ongoing teacher reflection are contributing factors to changes in teachers' motivational beliefs.

Accumulation and ordering of P3HT oligomers at the liquid-vapor interface with implications for thin-film morphology.

The morphology of semiconducting polymer thin films is known to have a profound effect on their opto-electronic properties. Although considerable efforts have been made to control and understand the processes which influence the structures of these systems, it remains largely unclear what physical factors determine the arrangement of polymer chains in spin-cast films. Here, we investigate the role that the liquid-vapor interfaces in chlorobenzene solutions of poly(3-hexylthiophene) [P3HT] play in the conformational geometries adopted by the polymers. Using all-atom molecular dynamics (MD), and supported by toy-model simulations, we demonstrate that, with increasing concentration, P3HT oligomers in solution exhibit a strong propensity for the liquid-vapor interface. Due to the differential solubility of the backbone and side chains of the oligomers, in the vicinity of this interface, hexyl chains and the thiophene rings, have a clear orientational preference with respect to the liquid surface. At high concentrations, we additionally establish a substantial degree of inter-oligomer alignment and thiophene ring stacking near the interface. Our results broadly concur with the limited existing experimental evidence and we suggest that the interfacial structure can act as a template for film structure. We argue that the differences in solvent affinity of the side chain and backbone moieties are the driving force for the anisotropic orientations of the polymers near the interface. This finer grained description contrasts with the usual monolithic characterization of polymer units. Since this phenomenon can be controlled by concurrent chemical design and the choice of solvents, this work establishes a fabrication principle which may be useful to develop more highly functional polymer films.

The effect of source backing materials and excitation pulse durations on laser-generated ultrasound waveforms.

In this article, it is shown experimentally that a planar laser-generated ultrasound source with a hard reflective backing will generate higher acoustic pressures than a comparable source with an acoustically matched backing when the stress confinement condition is not met. Furthermore, while the source with an acoustically matched backing will have a broader bandwidth when the laser pulse is short enough to ensure stress confinement, the bandwidths of both source types will converge as the laser pulse duration increases beyond stress confinement. The explanation of the results is supported by numerical simulations.

Use of locum doctors in NHS trusts in England: analysis of routinely collected workforce data 2019-2021.

OBJECTIVES: Temporary doctors, known as locum doctors, play an important role in the delivery of care in the National Health Service (NHS); however, little is known about the extent of locum use in NHS trusts. This study aimed to quantify and describe locum use for all NHS trusts in England in 2019-2021. SETTING: Descriptive analyses of data on locum shifts from all NHS trusts in England in 2019-2021. Weekly data were available for the number of shifts filled by agency and bank staff and the number of shifts requested by each trust. Negative binomial models were used to investigate the association between the proportion of medical staffing provided by locums and NHS trust characteristics. RESULTS: In 2019, on average 4.4% of total medical staffing was provided by locums, but this varied substantially across trusts (25th-75th centile=2.2%-6.2%). Over time, on average two-thirds of locum shifts were filled by locum agencies and a third by trusts' staff banks. On average, 11.3% of shifts requested were left unfilled. In 2019-2021, the mean number of weekly shifts per trust increased by 19% (175.2-208.6) and the mean number of weekly unfilled shifts per trust increased by 54% (32.7 to 50.4). Trusts rated by the Care Quality Commission (CQC) as inadequate or requiring improvement (incidence rate ratio=1.495; 95% CI 1.191 to 1.877), and smaller trusts had a higher use of locums. Large variability was observed across regions for use of locums, proportion of shifts filled by locum agencies and unfilled shifts. CONCLUSIONS: There were large variations in the demand for and use of locum doctors in NHS trusts. Trusts with poor CQC ratings and smaller trusts appear to use locum doctors more intensively compared with other trust types. Unfilled shifts were at a 3-year high at the end of 2021 suggesting increased demand which may result from growing workforce shortages in NHS trusts.

Sensitivity and Specificity of Different Prognostic Systems in Guiding Surveillance for Metastases in Uveal Melanoma.

Uveal melanoma (UM) metastasises in ~50% of patients, most frequently to the liver. Surveillance imaging can provide early detection of hepatic metastases; however, guidance regarding UM patient risk stratification for surveillance is unclear. This study compared sensitivity and specificity of four current prognostic systems, when used for risk stratification for surveillance, on patients treated at the Liverpool Ocular Oncology Centre (LOOC) between 2007-2016 (n = 1047). It found that the Liverpool Uveal Melanoma Prognosticator Online III (LUMPOIII) or Liverpool Parsimonious Model (LPM) offered greater specificity at equal levels of sensitivity than the American Joint Committee on Cancer (AJCC) system or monosomy 3 alone, and suggests guidance to achieve 95% sensitivity and 51% specificity (i.e., how to detect the same number of patients with metastases, while reducing the number of negative scans). For example, 180 scans could be safely avoided over 5 years in 200 patients using the most specific approach. LUMPOIII also offered high sensitivity and improved specificity over the AJCC in the absence of genetic information, making the result relevant to centres that do not perform genetic testing, or where such testing is inappropriate or fails. This study provides valuable information for clinical guidelines for risk stratification for surveillance in UM.

Participatory mapping to address neighborhood level data deficiencies for food security assessment in Southeastern Virginia, USA.

BACKGROUND: Food is not equitably available. Deficiencies and generalizations limit national datasets, food security assessments, and interventions. Additional neighborhood level studies are needed to develop a scalable and transferable process to complement national and internationally comparative data sets with timely, granular, nuanced data. Participatory geographic information systems (PGIS) offer a means to address these issues by digitizing local knowledge. METHODS: The objectives of this study were two-fold: (i) identify granular locations missing from food source and risk datasets and (ii) examine the relation between the spatial, socio-economic, and agency contributors to food security. Twenty-nine subject matter experts from three cities in Southeastern Virginia with backgrounds in food distribution, nutrition management, human services, and associated research engaged in a participatory mapping process. RESULTS: Results show that publicly available and other national datasets are not inclusive of non-traditional food sources or updated frequently enough to reflect changes associated with closures, expansion, or new programs. Almost 6 percent of food sources were missing from publicly available and national datasets. Food pantries, community gardens and fridges, farmers markets, child and adult care programs, and meals served in community centers and homeless shelters were not well represented. Over 24 km2 of participant identified need was outside United States Department of Agriculture low income, low access areas. Economic, physical, and social barriers to food security were interconnected with transportation limitations. Recommendations address an international call from development agencies, countries, and world regions for intervention methods that include systemic and generational issues with poverty, incorporate non-traditional spaces into food distribution systems, incentivize or regulate healthy food options in stores, improve educational opportunities, increase data sharing. CONCLUSIONS: Leveraging city and regional agency as appropriate to capitalize upon synergistic activities was seen as critical to achieve these goals, particularly for non-traditional partnership building. To address neighborhood scale food security needs in Southeastern Virginia, data collection and assessment should address both environment and utilization issues from consumer and producer perspectives including availability, proximity, accessibility, awareness, affordability, cooking capacity, and preference. The PGIS process utilized to facilitate information sharing about neighborhood level contributors to food insecurity and translate those contributors to intervention strategies through discussion with local subject matter experts and contextualization within larger scale food systems dynamics is transferable.