Can seasonal and interannual variation in landscape CO2 fluxes be detected by atmospheric observations of CO2 concentrations made at a tall tower?

The coupled numerical weather model WRF-SPA (Weather Research and Forecasting model and Soil-Plant-Atmosphere model) has been used to investigate a 3 yr time series of observed atmospheric CO₂ concentrations from a tall tower in Scotland, UK. Ecosystem-specific tracers of net CO₂ uptake and net CO₂ release were used to investigate the contributions to the tower signal of key land covers within its footprint, and how contributions varied at seasonal and interannual timescales. In addition, WRF-SPA simulated atmospheric CO₂ concentrations were compared with two coarse global inversion models, CarbonTrackerEurope and the National Oceanic and Atmospheric Administration's CarbonTracker (CTE-CT). WRF-SPA realistically modelled both seasonal (except post harvest) and daily cycles seen in observed atmospheric CO₂ at the tall tower (<i>R</i>² = 0.67, rmse = 3.5 ppm, bias = 0.58 ppm). Atmospheric CO₂ concentrations from the tall tower were well simulated by CTE-CT, but the inverse model showed a poorer representation of diurnal variation and simulated a larger bias from observations (up to 1.9 ppm) at seasonal timescales, compared to the forward modelling of WRF-SPA. However, we have highlighted a consistent post-harvest increase in the seasonal bias between WRF-SPA and observations. Ecosystem-specific tracers of CO₂ exchange indicate that the increased bias is potentially due to the representation of agricultural processes within SPA and/or biases in land cover maps. The ecosystem-specific tracers also indicate that the majority of seasonal variation in CO₂ uptake for Scotland's dominant ecosystems (forests, cropland and managed grassland) is detectable in observations within the footprint of the tall tower; however, the amount of variation explained varies between years. The between years variation in detectability of Scotland's ecosystems is potentially due to seasonal and interannual variation in the simulated prevailing wind direction. This result highlights the importance of accurately representing atmospheric transport used within atmospheric inversion models used to estimate terrestrial source/sink distribution and magnitude

Designing withdrawal support services for antidepressant users: Patients’ views on existing services and what they really need

BACKGROUND: Public Health England has recommended that services be put in place to support people who choose to withdraw from antidepressants because of a current gap. This study aims to explore the views of members of online withdrawal peer-support groups about existing healthcare and what additional support is needed. METHODS: The administrators of 15 online support groups for people stopping antidepressants were asked to advertise an online survey to their members. The survey, which was online from May 2021 to April 2022, was completed by 1276 people from 49 countries. RESULTS: 71% of respondents found their doctors' advice unhelpful (57% 'very unhelpful') regarding stopping an antidepressant; the main reasons being 'Recommended a reduction rate that was too quick for me', 'Not familiar enough with withdrawal symptoms to advise me' and 'Suggested stopping antidepressants would not cause withdrawal symptoms'. One in three did not seek advice from their prescriber when deciding whether to withdraw, with the main reasons being 'I felt they would not be supportive' (58%) and 'I felt that they didn't have the expertise to help me' (51%). The most common prescriber responses to those who did seek advice was 'Suggested a quick withdrawal schedule' (56%) and 'Not supportive and offered no guidance' (27%). The most common discontinuation periods recommended by doctors were one month (23%) and two weeks (19%). A range of potential professional services were rated 'very useful', most frequently: 'Access to smaller doses (e.g. tapering strips, liquid, smaller dose tablets) to ensure gradual reduction' (88%) and 'A health professional providing a personalised, flexible reduction plan' (79%). LIMITATIONS: This was a convenience sample, which may have been biased towards people who took longer to withdraw, and experienced more withdrawal symptoms, than antidepressant users in general. Black and ethnic minority people, and people without access to the internet, were underrepresented. CONCLUSIONS: Most participants reported their prescribers were unable to help them safely stop antidepressants, compelling them to turn to online peer-support groups instead. Our findings indicate, in keeping with previous studies, that clinicians require upskilling in safe tapering of antidepressants, and that patients need specialised services to help them stop safely

Survival outcomes and interval between lymphoscintigraphy and SLNB in cutaneous melanoma- findings of a large prospective cohort study

Introduction: Sentinel lymph node biopsy (SLNB) in cutaneous melanoma (CM) is performed to identify patient at risk of regional and distant relapse. We hypothesized that timing of lymphoscintigraphy may influence the accuracy of SLNB and patient outcomes. Methods: We reviewed prospective data on patients undergoing SLNB for CM at a large university cancer-center between 2008-2015, examining patient and tumor demographics and time between lymphoscintigraphy (LS) and SLNB. Kaplan-Meier survival analysis assessed disease-specific (DSS) and overall-survival (OS), stratified by timing of LS. Cox multivariate regression analysis assessed independent risk factors for survival. Results: We identified 1015 patients. Median follow-up was 45 months (IQR 26-68 months). Univariate analysis showed a 6.8% absolute DSS (HR 1.6 [1.03-2.48], p= 0.04) benefit and a 10.7% absolute OS (HR 1.64 [1.13-2.38], p=0.01) benefit for patients whose SLNB was performed 12 hours (n=652). Multivariate analysis identified timing of LS as an independent predictor of OS (p=0.007) and DSS (p=0.016) when competing with age, sex, Breslow thickness (BT) and SLN status. No difference in nodal relapse rates (5.2% v 4.6%; p=0.67) was seen. Both groups were matched for age, sex, BT and SLN status. Conclusion: These data have significant implications for SLNB services, suggesting delaying SLNB >12 hours after LS using a Tc99-labelled nanocolloid has a significant negative survival impact for patients and should be avoided. We hypothesise that temporal tracer migration is the underlying cause and advocate further trials investigating alternative, 'stable' tracer-agents