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The TROPOspheric Monitoring Instrument (TROPOMI) onboard the Sentinel-5 Precursor (S5P) satellite was launched on 13 October 2017 to provide the atmospheric composition for atmosphere and climate research. The S5P is a Sun-synchronous polar-orbiting satellite providing global daily coverage. The TROPOMI swath is 2600 km wide, and the ground resolution for most data products is 7.2×3.5 km2 (5.6×3.5 km2 since 6 August 2019) at nadir. The Finnish Meteorological Institute (FMI) is responsible for the development of the TROPOMI UV algorithm and the processing of the TROPOMI surface ultraviolet (UV) radiation product which includes 36 UV parameters in total. Ground-based data from 25 sites located in arctic, subarctic, temperate, equatorial and Antarctic areas were used for validation of the TROPOMI overpass irradiance at 305, 310, 324 and 380 nm, overpass erythemally weighted dose rate/UV index, and erythemally weighted daily dose for the period from 1 January 2018 to 31 August 2019. The validation results showed that for most sites 60 %–80 % of TROPOMI data was within ±20 % of ground-based data for snow-free surface conditions. The median relative differences to ground-based measurements of TROPOMI snow-free surface daily doses were within ±10 % and ±5 % at two-thirds and at half of the sites, respectively. At several sites more than 90 % of cloud-free TROPOMI data was within ±20 % of ground-based measurements. Generally median relative differences between TROPOMI data and ground-based measurements were a little biased towards negative values (i.e. satellite data < ground-based measurement), but at high latitudes where non-homogeneous topography and albedo or snow conditions occurred, the negative bias was exceptionally high: from −30 % to −65 %. Positive biases of 10 %–15 % were also found for mountainous sites due to challenging topography. The TROPOMI surface UV radiation product includes quality flags to detect increased uncertainties in the data due to heterogeneous surface albedo and rough terrain, which can be used to filter the data retrieved under challenging conditions.

The majority of ground-based aerosols observations are limited to fixed locations, narrowing the knowledge on their spatial variability. In order to overcome this issue, a compact Mobile Aerosol Monitoring System (MAMS) was developed to explore the aerosol vertical and spatial variability. This mobile laboratory is equipped with a micropulse lidar, a sun photometer and an aerosol spectrometer. It is distinguished from other transportable platforms through its ability to perform on-road measurements and its unique feature lies in the sun photometer's capacity for tracking the sun during motion. The system presents a great flexibility, being able to respond quickly in case of sudden aerosol events such as pollution episodes, dust, fire or volcano outbreaks. On-road mapping of aerosol physical parameters such as attenuated aerosol backscatter, aerosol optical depth, particle number and mass concentration and size distribution is achieved through the MAMS. The performance of remote sensing instruments on-board has been evaluated through intercomparison with instruments in reference networks (i.e. AERONET and EARLINET), showing that the system is capable of providing high quality data. This also illustrates the application of such a system for instrument intercomparison field campaigns. Applications of the mobile system have been exemplified through two case studies in northern France. MODIS AOD data was compared to ground-based mobile sun photometer data. A good correlation was observed with R2 of 0.76, showing the usefulness of the mobile system for validation of satellite-derived products. The performance of BSC-DREAM8b dust model has been tested by comparison of results from simulations for the lidar–sun-photometer derived extinction coefficient and mass concentration profiles. The comparison indicated that observations and the model are in good agreement in describing the vertical variability of dust layers. Moreover, on-road measurements of PM10 were compared with modelled PM10 concentrations and with ATMO Hauts-de-France and AIRPARIF air quality in situ measurements, presenting an excellent agreement in horizontal spatial representativity of PM10. This proves a possible application of mobile platforms for evaluating the chemistry-models performances.

Surface ultraviolet radiation (SUR) is not an increasing concern after the implementation of the Montreal Protocol and the recovery of the ozone layer Morgenstern et al.(2008). However, large uncertainties remain in the prediction of future changes of SUR Bais et al.(2015). Several studies pointed out that UV-B impacts the biosphere Erickson et al.(2015), especially the aquatic system, which plays a central part in the biogeochemical cycle Hader et al.(2007). It can affect phytoplankton productivity Smith and Cullen(1995). This influence can result in either positive or negative feedback on climate (Zepp et al., 2007). Global circulation model simulations predict an acceleration of the Brewer-Dobson circulation over the next century (Butchart, 2014), which would lead to a decrease in ozone levels in the tropics and an enhancement at higher latitudes (Hegglin and Shepherd, 2009). Reunion Island is located in the tropics (21° S, 55° E), in a part of the world where the amount of ozone in the ozone column is naturally low. In addition, this island is mountainous and the marine atmosphere is often clean with low aerosol concentrations. Thus, measurements show much higher SUR than at other sites at the same latitude or at midlatitudes. Ground-based measurements of SUR have been taken on Reunion Island by a Bentham DTMc300 spectroradiometer since 2009. This instrument is affiliated with the Network for the Detection of Atmospheric Composition Change (NDACC). In order to quantify the future evolution of SUR in the tropics, it is necessary to validate a model against present observations. This study is designed to be a preliminary parametric and sensitivity study of SUR modelling in the tropics. We developed a local parameterisation using the Tropospheric Ultraviolet and Visible Model (TUV; Madronich, 1993) and compared the output of TUV to multiple years of Bentham spectral measurements. This comparison started in early 2009 and continued until 2016. Only clear-sky SUR was modelled, so we needed to sort out the clear-sky measurements. We used two methods to detect cloudy conditions: the first was based on an observer's hourly report on the sky cover, while the second was based on applying Long and Ackerman(2000)'s algorithm to broadband pyranometer data to obtain the cloud fraction and then discriminating clear-sky windows on SUR measurements. Long et al. (2006)'s algorithm, with the co-located pyranometer data, gave better results for clear-sky filtering than the observer's report. Multiple model inputs were tested to evaluate the model sensitivity to different parameters such as total ozone column, aerosol optical properties, extraterrestrial spectrum or ozone cross section. For total column ozone, we used ground-based measurements from the SAOZ (Système d'Analyse par Observation Zénithale) spectrometer and satellite measurements from the OMI and SBUV instruments, while ozone profiles were derived from radio-soundings and the MLS ozone product. Aerosol optical properties came from a local aerosol climatology established using a Cimel photometer. Since the mean difference between various inputs of total ozone column was small, the corresponding response on UVI modelling was also quite small, at about 1 %. The radiative amplification factor of total ozone column on UVI was also compared for observations and the model. Finally, we were able to estimate UVI on Reunion Island with, at best, a mean relative difference of about 0.5 %, compared to clear-sky observations.

Spectral solar UV radiation measurements are performed in France using three spectroradiometers located at very different sites. One is installed in Villeneuve d'Ascq, in the north of France (VDA). It is an urban site in a topographically flat region. Another instrument is installed in Observatoire de Haute-Provence, located in the southern French Alps (OHP). It is a rural mountainous site. The third instrument is installed in Saint-Denis, Réunion Island (SDR). It is a coastal urban site on a small mountainous island in the southern tropics. The three instruments are affiliated with the Network for the Detection of Atmospheric Composition Change (NDACC) and carry out routine measurements to monitor the spectral solar UV radiation and enable derivation of UV index (UVI). The ground-based UVI values observed at solar noon are compared to similar quantities derived from the Ozone Monitoring Instrument (OMI, onboard the Aura satellite) and the second Global Ozone Monitoring Experiment (GOME-2, onboard the Metop-A satellite) measurements for validation of these satellite-based products. The present study concerns the period 2009–September 2012, date of the implementation of a new OMI processing tool. The new version (v1.3) introduces a correction for absorbing aerosols that were not considered in the old version (v1.2). Both versions of the OMI UVI products were available before September 2012 and are used to assess the improvement of the new processing tool. On average, estimates from satellite instruments always overestimate surface UVI at solar noon. Under cloudless conditions, the satellite-derived estimates of UVI compare satisfactorily with ground-based data: the median relative bias is less than 8 % at VDA and 4 % at SDR for both OMI v1.3 and GOME-2, and about 6 % for OMI v1.3 and 2 % for GOME-2 at OHP. The correlation between satellite-based and ground-based data is better at VDA and OHP (about 0.99) than at SDR (0.96) for both space-borne instruments. For all sky conditions, the median relative biases are much larger, with large dispersion for both instruments at all sites (VDA: about 12 %; OHP: 9 %; SDR: 11 %). Correlation between satellite-based and ground-based data is still better at VDA and OHP (about 0.95) than at SDR (about 0.73) for both satellite instruments. These results are explained considering the time of overpass of the two satellites, which is far from solar noon, preventing a good estimation of the cloud cover necessary for a good modelling of the UVI. Site topography and environment are shown to have a non-significant influence. At VDA and OHP, OMI v1.3 shows a significant improvement with respect to v1.2, which did not account for absorbing aerosols.

Routine sun-photometer and micro-lidar measurements were performed in Lille, northern France, in April and May 2010 during the Eyjafjallajökull volcanic eruption. The impact of such an eruption emphasized significance of hazards for human activities and importance of observations of the volcanic aerosol particles. This paper presents the main results of a joint micro-lidar/sun-photometer analysis performed in Lille, where volcanic ash plumes were observed during at least 22 days, whenever weather conditions permitted. Aerosol properties retrieved from automatic sun-photometer measurements (AERONET) were strongly changed during the volcanic aerosol plumes transport over Lille. In most cases, the aerosol optical depth (AOD) increased, whereas Ångström exponent decreased, thus indicating coarse-mode dominance in the volume size distribution. Moreover, the non-spherical fraction retrieved by AERONET significantly increased. The real part of the complex refractive index was up to 1.55 at 440 nm during the eruption, compared to background data of about 1.46 before the eruption. Collocated lidar data revealed that several aerosol layers were present between 2 and 5 km, all originating from the Iceland region as confirmed by backward trajectories. The volcanic ash AOD was derived from lidar extinction profiles and sun-photometer AOD, and its maximum was estimated around 0.37 at 532 nm on 18 April 2010. This value was observed at an altitude of 1700 m and corresponds to an ash mass concentration (AMC) slightly higher than 1000 μg m−3 (±50%). An effective lidar ratio of ash particles of 48 sr was retrieved at 532 nm for 17 April during the early stages of the eruption, a value which agrees with several other studies carried out on this topic. Even though the accuracy of the retrievals is not as high as that obtained from reference multiwavelength lidar systems, this study demonstrates the opportunity of micro-lidar and sun-photometer joint data processing for deriving volcanic AMC. It also outlines the fact that a network of combined micro-lidars and sun photometers can be a powerful tool for routine monitoring of aerosols, especially in the case of such hazardous volcanic events.

We present ground-based measurements of aerosol mass, optical properties and vertical extinction profiles acquired in M'Bour, Senegal (16.96° W; 14.39° N) from January 2006 to September 2008. This place of the world is all year long affected by the export of mineral dust as it moves westward to the north Atlantic ocean. The maximum in the dust activity is observed in summer (June–July), corresponding to a maximum in the aerosol optical thickness (above 0.5) and single scattering albedo (above 0.95). It also corresponds to a maximum in the top altitude of the transported aerosol layer (up to 6 km) and aerosol optical thickness scale height (up to 3.5 km) due to the presence of the Saharan Air Layer located between 2 and 6 km. The late summer shows an additional low level aerosol layer that increases in thickness in autumn. Severe dust storms are also systematically observed in spring (March) but with a lower vertical development and a stronger impact (factor 2 to 3) on the ground-level mass compared to summer. Sporadic events of biomass burning aerosols are observed in winter (January) and particularly in January 2006 when the biomass burning aerosol are advected between 1.5 and 3.5 km high. On average, the seasonal signal in the aerosol optical properties and vertical distribution is very similar from year to year over our 3 year monitoring.

We examine three supernova remnants in the SMC, IKT 5 (supernova remnant (SNR) 0047-73.5), IKT 25 (SNR 0104-72.3), and DEM S 128 (SNR 0103-72.4), which are designated as Type Ia in the literature due to their spectra and morphology. This is troublesome because of their asymmetry, a trait not usually associated with young Type Ia remnants. We present Chandra X-ray Observatory data on these three remnants and perform a maximum likelihood analysis on their spectra. We find that the X-ray emission is dominated by interactions with the interstellar medium. In spite of this, we find a significant Fe overabundance in all three remnants. Through examination of radio, optical, and infrared data, we conclude that these three remnants are likely not Type Ia SNRs. We detect potential point sources that may be members of the progenitor systems of both DEM S 128 and IKT 5, which could suggest these could be Fe-rich core-collapse remnants. [ABSTRACT FROM AUTHOR]

Olfactory perception begins when odorous substances interact with specialized receptors located on the surface of dedicated sensory neurons. The recognition of smells depends on a complex mechanism involving a combination of interactions between an odorant and a set of odorant receptors (ORs), where molecules are recognized according to a combinatorial activation code of ORs. Although these interactions have been studied for decades, the rules governing this ligand recognition remain poorly understood, and the complete combinatorial code is only known for a handful of odorants. We have carefully analyzed experimental results regarding the interactions between ORs and molecules to provide a status report on the deorphanization of ORs, i.e., the identification of the first agonist for a given sequence. This meticulous analysis highlights the influence of experimental methodology (cell line or readout) on molecule-receptor association results and shows that 83% of the results are conserved regardless of experimental conditions. The distribution of another key parameter, EC50, indicates that most OR ligands activities are in the micromolar range and that impurities could lead to erroneous conclusions. Focusing on the human ORs, our study shows that 88% of the documented sequences still need to be deorphanized. Finally, we also estimate the size of the ORs' recognition range, or broadness, as the number of odorants activating a given OR. By analogously estimating molecular broadness and combining the two estimates we propose a basic framework that can serve as a comparison point for future machine learning algorithms predicting OR-molecule activity., (© The Author(s) 2024. Published by Oxford University Press. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Phenomenon: Despite the importance of diet in the prevention and management of many common chronic diseases, nutrition training in medicine is largely inadequate in medical school and residency. The emerging field of culinary medicine offers an experiential nutrition learning approach with the potential to address the need for improved nutrition training of physicians. Exploring this innovative nutrition training strategy, this scoping review describes the nature of culinary medicine experiences for medical students and resident physicians, their impact on the medical trainees, and barriers and facilitators to their implementation., Approach: This scoping review used the Joanna Briggs Institute methodology for scoping reviews and the Preferred Reporting Items for Systematic Reviews and Meta-analyses extension for Scoping Reviews (PRISMA-ScR) checklist as guides. Eligible publications described the nature, impact, facilitators, and/or barriers of nutrition and food preparation learning experiences for medical students and/or residents. Additional inclusion criteria were location (U.S. or Canada), allopathic or osteopathic, English, human subjects, and publication year (2002 or later). The search strategy included 4 electronic databases. Two reviewers independently screened titles/abstracts and a third reviewer resolved discrepancies. The full-text review consisted of 2 independent reviews with discrepancies resolved by a third reviewer or by consensus if needed, and the research team extracted data from the included articles based on the nature, impact, barriers, and facilitators of culinary medicine experiences for medical trainees., Findings: The publication search resulted in 100 publications describing 116 experiences from 70 institutions. Thirty-seven publications described pilot experiences. Elective/extracurricular and medical student experiences were more common than required and resident experiences, respectively. Experiences varied in logistics, instruction, and curricula. Common themes of tailored culinary medicine experiences included community engagement/service-based learning, interprofessional education, attention to social determinants of health, trainee well-being, and cultural considerations. Program evaluations commonly reported the outcome of experiences on participant attitudes, knowledge, skills, confidence, and behaviors. Frequent barriers to implementation included time, faculty, cost/funding, kitchen space, and institutional support while common facilitators of experiences included funding/donations, collaboratives and partnerships, teaching kitchen access, faculty and institutional support, and trainee advocacy., Insights: Culinary medicine is an innovative approach to address the need and increased demand for improved nutrition training in medicine. The findings from this review can guide medical education stakeholders interested in developing or modifying culinary medicine experiences. Despite barriers to implementation, culinary medicine experiences can be offered in a variety of ways during undergraduate and graduate medical education and can be creatively designed to fulfill some accreditation standards.

Solar UV radiation causes beneficial and detrimental changes in human health. International and national Health agencies recommend avoiding sun exposure when the solar rays are strongest (typically 2 h before and after solar noon). In this study we detail and refine such recommendations. We estimated biologically-effective radiation (inductive of erythema and pre-vitamin D) using spectral solar UV radiation measurements on a horizontal plane at three French sites equipped with spectroradiometers: Villeneuve d'Ascq (VDA) (North of France); Observatoire de Haute-Provence (OHP) (French Southern Alps); and Saint-Denis de La Réunion (SDR) on Réunion Island, in the Indian Ocean. These sites are very different: VDA is a semi-urban site in a flat region, OHP a rural mountainous site and SDR a coastal urban site on a small mountainous island. Biologically active radiation was analyzed by studying erythema induction and measuring pre-vitamin D synthesis. Dose-rates, doses and times for sunburn induction and vitamin D production were derived. Regarding the level of vitamin D dose considered here (1000 IU), we found that at mainland sites time required for vitamin D synthesis was relatively long, even around solar noon, in winter months this could be 2-3 h for phototype II individuals exposing their face and hands. In the tropics vitamin D could always be synthesized in a reasonable time (e.g. 20 min in winter). By contrast, in summer, the required duration times (exposing face, hands, arms and legs) are very short, approximately 2-4 min on the mainland and 1 min in the tropics for phototype II individuals. In all skin phototypes the duration of sun exposure required to induce erythema was generally longer than that to produce vitamin D. These quantitative results, obtained using an instrument measuring on a horizontal plane and with an unobstructed view, do not represent realistic values for human exposure. To account for realistic human body exposure, received doses and times of exposure were adjusted. Our study shows that, mostly in summer, the time periods where limited solar exposure is recommended should be extended, especially at low latitude locations., (Copyright © 2021 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: Given their profound emotional, physical, and financial toll on patients and surgeons, we studied the characteristics, costs, and contributing factors of thyroid and parathyroid surgical malpractice claims., Methods: Using the Controlled Risk Insurance Company Strategies' Comparative Benchmarking System database, representing ~30% of all US paid and unpaid malpractice claims, 5384 claims filed against general surgeons and otolaryngologists from 1995-2015 were reviewed to isolate claims involving the surgical management of thyroid and parathyroid disease. These claims were studied, and multivariable regression analysis was performed to identify factors associated with plaintiff payout., Results: One hundred twenty-eight thyroid and parathyroid surgical malpractice claims were isolated. The median time from alleged harm event to closure of a malpractice case was 39 months. The most common associated complications were bilateral recurrent laryngeal nerve (RLN) injury (n = 23) and hematoma (n = 18). Complications led to death in 18 cases. Patient payout occurred in 33% of claims (n = 42), and the median cost per claim was $277,913 (IQR $87,343-$783,663). On multivariable analysis, bilateral RLN injury was predictive of patient payout (OR 3.58, p = 0.03), while procedure, death, and surgeon specialty were not., Conclusion: Though rare, malpractice claims related to thyroid and parathyroid surgery are costly, time-consuming, and reveal opportunities for early surgeon-patient resolution after poor outcomes.

Objective: We aimed to study the contributing factors and costs of malpractice claims involving the surgical management of benign biliary disease given the emotional, physical, and financial toll of these claims on patients, providers, and the healthcare system., Summary Background Data: Cholecystectomy complications carry significant morbidity and rank among the leading sources of surgical malpractice claims., Methods: Using the CRICO Strategies' Comparative Benchmarking System database, representing approximately 30% of all paid and unpaid malpractice claims in the United States, 4081 closed claims filed against general surgeons from 1995 to 2015 were reviewed to isolate 745 cholecystectomy-related claims. A multivariable model was used to determine factors associated with claim outcome., Results: The most common associated complications included bile duct injury (n = 397), bowel perforation (n = 96), and hemorrhage (n = 78). Bile duct injuries were recognized intraoperatively only 19% of the time and required biliary reconstruction surgery 77% of the time. The total cost for all claims over the study period was over $128 M and the median time from event to case close was over 3 years. 40% of claims resulted in patient payout; of these, most claims were settled out of court and the median cost per claim was $264,650. For the 60% of claims not resulting in patient payout, most cases were denied, dropped, or dismissed, yet still averaged over $15,000 per claim in legal and administrative fees. On multivariable analysis, bile duct injury, bowel perforation, and high clinical severity were associated with patient payout, while a resident or fellow being named in a claim was negatively associated with patient payout (P < 0.05)., Conclusion: Cholecystectomy-related claims are costly and time-consuming. Strategies that reduce the risk and aid in recognition of cholecystectomy complications, as well as advance support of patients and families after poor outcomes, may improve clinical care and reduce claim burden.

Purpose: Medical errors in radiation oncology (RO) practice have received significant national attention over the last decade. Medical errors can lead to malpractice cases. Better characterizing these events can educate providers with the goal of improving patient care., Methods and Materials: The Controlled Risk Insurance Company Strategies' Comparative Benchmarking System (CBS) represents approximately 30% of all closed US malpractice cases and includes the experience of more than 30 academic hospitals. Registered nurses trained as clinical taxonomy specialists code each case, and individual case-level details are available. Practicing radiation oncologists extracted all closed RO cases from years 2005 to 2014 and subgrouped them by patient allegation category, clinical injury severity, care setting and academic affiliation, disease site and natural history, treatment modality, and contributing factor. Within categories, χ 2 tests were used to test for the variables' association with an indemnity payment., Results: RO was the primary service in 102 closed cases (0.2% of all cases in the CBS), accounting for $13,323,578 in indemnity payments (0.1% of all payments in the CBS). The median indemnity payment was $100,000. Head-and-neck and central nervous system tumors accounted for 23.9% and 10.9% of all RO cases, respectively, and 41.3% and 31.4% of all indemnity payments, respectively. Benign diseases and brachytherapy were involved in 12.0% and 15.2% of cases, respectively. Cases involving benign disease (P = .009), treatment of the wrong site (P = .001), or treatment using the wrong dose (P < .001) were all associated with indemnity payments. The top 5 most expensive cases accounted for nearly 80% of all indemnity payments, and all involved head-and-neck, central nervous system, benign, or brachytherapy cases., Conclusions: We found that although closed malpractice cases involving RO are rare events, certain populations may be overrepresented in closed claims. These data can help inform providers and systems with the goal of ultimately improving patient safety., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Just as radiologic studies allow us to see past the surface to the vulnerable and broken parts of the human body, medical malpractice claims help us see past the surface of medical errors to the deeper vulnerabilities and potentially broken aspects of our healthcare delivery system. And just as the insights we gain through radiologic studies provide focus for a treatment plan for healing, so too can the analysis of malpractice claims provide insights to improve the delivery of safe patient care. We review 1325 coded claims where Radiology was the primary service provider to better understand the problems leading to patient harm, and the opportunities most likely to improve diagnostic care in the future.

To estimate potential sunburn risk for schoolchildren and outdoor workers, ground-based ambient solar ultraviolet radiation (UVR) measurements were converted into possible child (5% of ambient solar UVR) and outdoor worker (20% of ambient solar UVR) solar UVR exposures by skin type and season for three coastal sites: Durban, Cape Point (South Africa) and Saint Denis (Reunion Island, France). Cumulative daily ambient solar UVR levels were relatively high at all sites, especially during summer, with maximum values of about 67, 57 and 74 Standard Erythemal Dose (SED) (1 SED = 100 J m(-2)) at Durban, Cape Point and Saint Denis respectively. Sunburn risk was evident for both children and outdoor workers, especially those with skin types I and II (extremely to moderately sensitive) during summer, early autumn and/or late spring at all three sites. Although results need to be verified with real-time, instantaneous and nonintegrated personal solar UVR measurements, this understanding of sunburn risk is useful for initiating the development skin cancer prevention and sun protection awareness campaigns in both countries., (© 2013 The American Society of Photobiology.)