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The accuracy of surface reflectance estimation for satellite sensors using radiance-based calibrations can depend significantly on the choice of solar spectral irradiance (or solar spectrum) model used for atmospheric correction. Selecting an accurate solar spectrum model is also important for radiance-based sensor calibration and estimation of atmospheric parameters from irradiance observations. Previous research showed that Landsat 8 could be used to evaluate the quality of solar spectrum models. This paper applies the analysis using five previously evaluated and three more recent solar spectrum models using both Landsat 8 (OLI) and Landsat 9 (OLI2). The study was further extended down to 10 nm resolution and a wavelength range from Ultraviolet A (UVA) to shortwave infrared (SWIR) (370–2480 nm) using inversion of field irradiance measurements. The results using OLI and OLI2 as well as the inversion of irradiance measurements were that the more recent Chance and Kurucz (SA2010), Meftah (SOLAR-ISS) and Coddington (TSIS-1) models performed better than all of the previous models. The results were illustrated by simulating dark and bright surface reflectance signatures obtained by atmospheric correction with the different solar spectrum models. The results showed that if the SA2010 model is assumed to be the “true” solar irradiance, using the TSIS-1 or the SOLAR-ISS model will not significantly change the estimated ground reflectance. The other models differ (some to a large extent) in varying wavelength areas.

ObjectiveTo quantify risk of colorectal cancer (CRC) at empirical FIT cut offs, across age, haemoglobin and platelet strata in current diagnostic pathways.DesignCohort study of all people who were referred on a symptomatic CRC diagnosis pathway from primary care with a FIT test in Nottingham, UK between November 2017 and 2021 with 1-year follow-up for cancer and death. Heat maps showed the cumulative 1-year CRC risk using Kaplan-Meier estimates. We estimated the number of investigations that could potentially be re-purposed if a threshold of ≥3% 1-year risk of CRC was instigated.ResultsDuring the study period 514 (1.5%) colorectal cancers were diagnosed following 33694 index FIT tests with available blood tests. Individuals with a FIT ≥10 μg Hb/g faeces had a greater than 3% risk of CRC, except patients under the age of 40 years (CRC risk 1.45% (95% CI 0.03-2.86%)). Non-anaemic patients with a FIT ConclusionsCRC risk varies by FIT, age and anaemia status when fHb levels are below 100 μg Hb/g faeces. Tailored cut offs for investigation on a CRC pathway could reduce the number of investigations needed at a 3% CRC risk threshold.What is already known on this topicThe National Institute for Health and Care Excellence (NICE), the joint Association of Coloproctology of Great Britain & Ireland and the British Society of Gastroenterology guidelines and the Welsh Government recommend a FIT cut off of ≥10 μg Hb/g faeces for investigation of CRC on an urgent pathway based on an expected colorectal cancer risk threshold of 3%. However, empirical evidence of this threshold in practice and the impact of age, anaemia and thrombocytosis upon it is lacking.What this study addsPeople who had a FIT test in primary care in Nottingham between 2017 and 2021 had a 1- year risk of colorectal cancer of just 1.5%.Non-anaemic patients over 70 years old do not meet the 3% threshold set by NICE for urgent investigation until they have a FIT greater than 40 μg Hb/g faeces.Patients under 40 years of age only meet the 3% threshold for investigation when they have a FIT ≥100 μg Hb/g faeces and are anaemic.How this study might affect research, practice or policyWe estimate that by using a stratified approach to meet the ≥3% risk of CRC threshold that includes FIT, age and anaemia rather than a single cut off for FIT of ≥10 μg Hb/g faeces will allow the optimum number of cancers to be diagnosed for the investigations undertaken.This study assessed existing empirical categorisations of FIT, age and anaemia. Ideally, further optimisation and validation of pathways could be achieved by deriving cut offs and strata using continuous modelling of FIT, age and blood test results.The balance of investigations required, cancers diagnosed and missed is crucial to consider when attempting to optimise diagnostic accuracy and health service provision in the real world. Consensus among all stakeholders needs to be reached on the threshold (risk of CRC) at which investigation should be triggered, taking all these factors into account.

Delineating the spatial ecology of elasmobranchs is an important precursor to their effective management. Establishing long-term patterns in the habitat use of several threatened species can focus management to yield increased conservation benefits. We completed 738 transects on 16 reef sites off the coast of southern Mozambique to record encounters with elasmobranch species and 12 environmental and spatiotemporal parameters (location, time, day, tide and range, cloud cover, visibility, lunar phase, temperature, current strength, and direction, transect duration). The influence of the measured parameters on the visit frequencies of nine regularly (> 20 / year) encountered elasmobranch species (Carcharhinus amblyrhynchos, Triaenodon obesus, Stegastoma tigrinum, Neotrygon kuhlii, Himantura jenkinsii, Taeniura meyeni, Mobula kuhlii, Mobula alfredi, Mobula birostris) were estimated using multivariate models. All species, bar H. jenkinsii, frequented specific reef sites. Counts were generally highest in summer. Three species (M. birostris, M. kuhlii, S. tigrinum) counts peaked in winter. T. obesus and M. alfredi tended to frequent reefs during high tides, M. kuhlii during slack tides, N. kuhlii during low tides and C. amblyrhynchos when the tidal range was high. Counts of M. alfredi were highest during full moons and M. kuhlii during full, half, and new moons. Non-Metric Multidimensional Scaling (NMDS) indicated that species responses to the measured parameters grouped taxonomically. Environmental influences resulted in daily, monthly, and seasonal patterns of reef use. Our results indicate that specific elasmobranch species routinely congregate on specific reef sites and that management of these sites could promote several threatened populations.

Objectives Currently, NICE recommends the use of faecal immunochemical test (FIT) at faecal haemoglobin concentrations (f-Hb) of 10 μg Hb/g faeces to stratify for colorectal cancer (CRC) risk in symptomatic populations. This f-Hb cut-off is advised across all analysers, despite the fact that a direct comparison of analyser performance, in a clinical setting, has not been performed. Methods Two specimen collection devices (OC-Sensor, OC-S; HM-JACKarc, HM-J) were sent to 914 consecutive individuals referred for follow up due to their increased risk of CRC. Agreement of f-Hb around cut-offs of 4, 10 and 150 µg Hb/g faeces and CRC detection rates were assessed. Two OC-S devices were sent to a further 114 individuals, for within test comparisons. Results A total of 732 (80.1%) individuals correctly completed and returned two different FIT devices, with 38 (5.2%) CRCs detected. Median f-Hb for individuals diagnosed with and without CRC were 258.5 and 1.8 µg Hb/g faeces for OC-S and 318.1 and 1.0 µg Hb/g faeces for HM-J respectively. Correlation of f-Hb results between OC-S/HM-J over the full range was rho=0.74, p Conclusions We found large variations in f-Hb when different FIT devices were used, but a smaller variation when the same FIT device was used. Our data suggest that analyser-specific f-Hb cut-offs are applied with regard to clinical decision making, especially at lower f-Hb.

AIM We introduced primary care access to faecal immunochemical testing (FIT) as a stratification tool for symptomatic patients considered to be at risk of colorectal cancer (CRC) prior to urgent referral. We aimed to evaluate clinical and pathway outcomes during the first 6 months of this novel approach. METHOD FIT was recommended for all patients who consulted their general practitioner with lower gastrointestinal symptoms other than rectal bleeding and rectal mass. We undertook a retrospective audit of the results of FIT, related clinical outcomes and resource utilization on prospectively logged cases between November 2017 and May 2018. RESULTS Of the 1862 FIT kits dispatched by post 91.4% were returned, with a median return time of 7 days (range 2-110 days); however, 1.3% of returned kits could not be analysed. FIT results ≥ 150.0 μg haemoglobin (Hb)/g faeces identified patients with a significantly higher risk of CRC (30.9% vs 1.4%, chi-square 167.1, P

Background New national guidance on urgent referral for investigation of colorectal cancer included faecal occult blood testing in 2015. A service evaluation of faecal immunochemical testing (FIT) and anaemia as risk stratification tools in symptomatic patients suspected of having CRC was undertaken. Methods Postal FIT was incorporated into the colorectal cancer 2-week wait (2WW) pathway for all patients without rectal bleeding in 2016. Patients were investigated in the 2WW pathway as normal, and outcomes of investigations were recorded prospectively. Anaemia was defined as a haemoglobin level below 120 g/l in women and 130 g/l in men. Results FIT kits were sent to 1106 patients, with an 80·9 per cent return rate; 810 patients completed investigations and 40 colorectal cancers were diagnosed (4·9 per cent). FIT results were significantly higher in patients with anaemia (median (i.q.r.) 4·8 (0·8-34·1) versus 1·2 (0-6·4) μg Hb/g faeces in those without anaemia; P

Synucleinopathies are a heterogeneous group of neurodegenerative diseases with amyloid deposits that contain the α-synuclein (SNCA/α-Syn) protein as a common hallmark. It is astonishing that aggregates of a single protein are able to give rise to a whole range of different disease manifestations. The prion strain hypothesis offers a possible explanation for this conundrum. According to this hypothesis, a single protein sequence is able to misfold into distinct amyloid structures that can cause different pathologies. In fact, a growing body of evidence suggests that conformationally distinct α-Syn assemblies might be the causative agents behind different synucleinopathies. In this review, we provide an overview of research on the strain hypothesis as it applies to synucleinopathies and discuss the potential implications for diagnostic and therapeutic purposes.

ObjectiveService evaluation of GP access to Faecal Immunochemical Test (FIT) for colorectal cancer (CRC) detection in Nottinghamshire and use of FIT for “rule out”, “rule in” and “first test selection”.DesignRetrospective audit of FIT results, CRC outcomes and resource utilisation before and after introduction of FIT in Primary Care in November 2017. Data from the new pathway up to December 2018 was compared with previous experience.ResultsBetween November 2017 and December 2018, 6747 GP FIT test requests yielded 5733 FIT results, of which 4082 (71.2%) were [less than]4.0 μg Hb/g faeces, 579 (10.1%) were 4.0–9.9 μg Hb/g faeces, 836 (14.6%) were 10.0–149.9 μg Hb/g faeces, and 236 (4.1%) were ≥150.0 μg Hb/g faeces. The proportion of “rule out” results [less than]4.0 μg Hb/g faeces was significantly higher than in the Getting FIT cohort (71.2% vs 60.4%, Chi squared 42.8, p [less than] 0.0001) and the proportion of “rule in” results ≥150.0 μg Hb/g faeces was significantly lower (4.1% vs 8.1%, Chi squared 27.3,P [less than] 0.0001).There was a 33% rise in urgent referrals across Nottingham overall during the evaluation period. 2 CRC diagnoses were made in 4082 patients who had FIT[less than]4.0 μg Hb/g faeces. 58.4% of new CRC diagnoses associated with a positive FIT were early stage cancers (Stage I and II). The proportion of all CRC diagnoses that follow an urgent referral s rose after introduction of FIT.ConclusionsFIT allows GP's to select a more appropriate cohort for urgent investigation without a large number of missed diagnoses. FIT appears to promise a “stage migration” effect which may ultimately improve CRC outcomes.

Background A novel pathway incorporating faecal immunochemical testing (FIT) for rapid colorectal cancer diagnosis (RCCD) was introduced in 2017. This paper reports on the service evaluation after 2 years of pathway implementation. Methods The RCCD protocol was based on FIT, blood results and symptoms to stratify adult patients in primary care. Two-week-wait (2WW) investigation was indicated for patients with rectal bleeding, rectal mass and faecal haemoglobin (fHb) level of 10 µg Hb/g faeces or above or 4 µg Hb/g faeces or more in the presence of anaemia, low ferritin or thrombocytosis, in all other symptom groups. Patients with 100 µg Hb/g faeces or above had expedited investigation . A retrospective audit of colorectal cancer detected between 2017 and 2019 was conducted, fHb thresholds were reviewed and critically assessed for cancer diagnoses. Results In 2 years, 14788 FIT tests were dispatched with 13361 (90.4 per cent) completed returns. Overall, fHb was less than 4 µg Hb/g faeces in 9208 results (68.9 per cent), 4–9.9 µg Hb/g in 1583 (11.8 per cent), 10–99.9 µg Hb/g in 1850 (13.8 per cent) and 100 µg Hb/g faeces or above in 720 (5.4 per cent). During follow-up (median 10.4 months), 227 colorectal cancers were diagnosed. The cancer detection rate was 0.1 per cent in patients with fHb below 4 µg Hb/g faeces, 0.6 per cent in those with fHb 4–9.9 µg Hb/g faeces, 3.3 per cent for fHb 10–99.9 µg Hb/g faeces and 20.7 per cent for fHb 100 µg Hb/g faeces or above. The detection rate in the cohort with 10–19.9 µg Hb/g faeces was 1.4 per cent, below the National Institute for Health and Care Excellence threshold for urgent referral. The colorectal cancer rate in patients with fHb below 20 µg Hb/g faeces was less than 0.3 per cent. Conclusion Use of FIT to "rule out" urgent referral from primary care misses a small number of cases. The threshold for referral may be adjusted with blood results to improve stratification ., We present outcome data from a service evaluation that demonstrates clinical effectiveness and safety. This strategy may be crucial to overcoming the effects of the Coronavirus pandemic on 2WW and urgent pathways.

Supplemental Material, Appendix_2b_R2 for Economic burden of migraine in Singapore by Jonathan Jia Yuan Ong, Devanshi Patnaik, Yee Cheun Chan, Oliver Simon and Eric A Finkelstein in Cephalalgia Reports