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Small unmanned aerial systems (sUASs) are becoming very popular as affordable and reliable observation platforms. The Lower Atmospheric Process Studies at Elevation – a Remotely-piloted Aircraft Team Experiment (LAPSE-RATE), conducted in the San Luis Valley (SLV) of Colorado (USA) between 14 and 20 July 2018, gathered together numerous sUASs, remote-sensing equipment, and ground-based instrumentation. Flight teams from the Finnish Meteorological Institute (FMI) and the Kansas State University (KSU) co-operated during LAPSE-RATE to measure and investigate the properties of aerosol particles and gases at the surface and in the lower atmosphere. During LAPSE-RATE the deployed instrumentation operated reliably, resulting in an observational dataset described below in detail. Our observations included aerosol particle number concentrations and size distributions, concentrations of CO2 and water vapor, and meteorological parameters. All datasets have been uploaded to the Zenodo LAPSE-RATE community archive (https://zenodo.org/communities/lapse-rate/, last access: 21 August 2020). The dataset DOIs for FMI airborne measurements and surface measurements are available here: https://doi.org/10.5281/zenodo.3993996, Brus et al. (2020a), and those for KSU airborne measurements and surface measurements are available here: https://doi.org/10.5281/zenodo.3736772, Brus et al. (2020b).

Unmanned aerial systems (UASs) are increasingly being used as observation platforms for atmospheric applications. The Lower Atmospheric Process Studies at Elevation – a Remotely-piloted Aircraft Team Experiment (LAPSE-RATE) in Alamosa, Colorado, USA, on 14–20 July 2018 investigated and validated different UASs, measurement sensors and setup configurations. Flight teams from the Finnish Meteorological Institute (FMI) and Kansas State University (KSU) participated in LAPSE-RATE to measure and investigate properties of aerosol particles and gases in the lower atmosphere. During the experiment, the performance of different UAS configurations were investigated and confirmed to operate reliably, resulting in a scientifically sound observational dataset. As an example, concentration of aerosols – including two new particle formation events, CO2 and water vapor, and meteorological parameters in the atmospheric vertical profile were measured during the short experiment. Such observations characterizing atmospheric phenomena of this specific environment would have not been possible in any other way and, thus, demonstrate the power of UASs as new, promising tools in atmospheric and environmental research.

IntroductionPrevious studies reported that the coronavirus disease (COVID-19) pandemic has negatively affected the mental health of employees in the hospitality industry internationally, however, its effect in Sweden has not been studied. Unlike several other countries, Sweden never enforced a lockdown. Restaurants, bars, and hotels could remain open and host a limited number of guests but had to abide by certain restrictions.MethodsA cross-sectional survey was distributed among hospitality industry employees containing questions regarding the perceived effects of the pandemic on the respondents’ working and life situations and their physical and psychological health. The sample consisted of 699 individuals, with a response rate of 47.9%.ResultsAlthough several respondents had been laid off or furloughed, the majority of the sample remained at the same employer. However, more than half of the respondents reported that their economic situation had deteriorated. Compared to before the pandemic, 38.1% experienced elevated levels of stress, 48.3% experienced elevated levels of worry, and 31.4% reported worsened mood. A deteriorating personal economy and difficulty in following COVID-19-related restrictions at work were associated with the worsening of these three mental health aspects. While the fear of becoming infected with COVID-19 was related to higher levels of stress, the fear of infecting others was related to higher levels of worry.ConclusionAlthough Sweden imposed less strict measures than most other countries, the personal economy and mental health of hospitality workers were negatively affected by the COVID-19 pandemic.

A full-thickness biopsy of the bowel wall is required to evaluate the enteric nervous system. A patient with aggravating gastrointestinal symptoms underwent a laparoscopic full-thickness biopsy of the ileum and, 1 year later, an endoscopic full-thickness biopsy of the sigmoid colon. Both samples showed enteric neuropathy characterized by vacuolated and enlarged neurons. The length of the myenteric plexus was greater in the endoscopic (23 mm) compared to the laparoscopic (11 mm) biopsy, with fewer tissue artefacts in the laparoscopic approach. Clinical deterioration was paralleled by enteric neuropathy with an increase in the percentage of vacuolated and enlarged enteric neurons from 24 to 35%.

The hygroscopicity of mineral aerosol samples has been examined by three independent methods: diffuse reflectance infrared Fourier transform spectroscopy, thermogravimetric analysis and differential mobility analysis. All three methods allow an evaluation of the water coverage of two samples, CaCO3 and Arizona Test dust, as a function of relative humidity. For the first time, a correlation between absolute gravimetric measurements and the other two (indirect) methods has been established. Water uptake isotherms were reliably determined for both solids which at 298 K and 80% relative humidity exhibited similar coverages of ~4 monolayers. However, the behaviour at low relative humidity was markedly different in the two cases, with Arizona Test Dust showing a substantially higher affinity for water in the contact layer. This is understandable in terms of the chemical composition of these two materials. The mobility analysis results are in good accord with field observations and with our own spectroscopic and gravimetric measurements. These findings are of value for an understanding of atmospheric chemical processes.

BACKGROUND: Microscopic colitis (MC) is a disease manifested by diarrhoea and is divided into collagenous and lymphocytic colitis. The aetiology is unknown, but auto-immunity is suggested. Auto-antibodies have been only rarely examined in this entity. The aim of the study was to examine the prevalence of auto-antibodies, and to examine associations between the presence of antibodies and clinical findings. METHODS AND FINDINGS: Women with MC verified by biopsy and younger than 73 years, at any Department of Gastroenterology, in the district of Skåne, between 2002 and 2010 were invited to participate in this study. The patients were asked to complete both a questionnaire describing their medical history and the Gastrointestinal Symptom Rating Scale (GSRS). Blood samples were collected. Anti-nuclear antibodies (ANA), anti-neutrophil cytoplasmic antibodies (ANCA), anti-Saccharomyces cerevisiae antibodies (ASCA), and antibodies against glutamic acid decarboxylase (anti-GAD), islet antigens-like insulin 2 (anti-IA2), thyroid peroxidase (anti-TPO), and thyrotropin receptor (TRAK) were analysed. Of 240 women identified, 133 were finally included in the study, median age 63 (59-67) years. Apart from the MC diagnosis, 52% also suffered from irritable bowel syndrome, 31% from hypertension and 31% from allergy. The prevalence of ANA (14%), ASCA IgG (13%), and anti-TPO antibodies (14%) for these patients was slightly higher than for the general population, and were found together with other concomitant diseases. Patients had more of all gastrointestinal symptoms compared with norm values, irrespective of antibody expression. CONCLUSIONS: Women with MC have a slightly increased prevalence of some auto-antibodies. These antibodies are not associated with symptoms, but are expressed in patients with concomitant diseases, obscuring the pathophysiology and clinical picture of MC.

Background and aims. Microscopic colitis (MC), predominantly affecting women, is associated with thyroid disorders, although purely defined of which type, or compared with controls. Its association with subclinical thyroid disorders, and related increased risk of cardiovascular diseases, has never been examined. The aim was to examine the prevalence of autoantibodies and subclinical and clinical thyroid dysfunction in female patients with MC compared with controls. Methods. Women younger than 73 years old with biopsy-verified MC from the Department of Gastroenterology in Skane, during 2002-2010, were invited. Out of 240 identified, 133 were finally included. A questionnaire about medical history was completed and blood samples were collected. Serum was analyzed for free thyroxin and triiodothyronine, thyroid-stimulating hormone and antithyroid peroxidase (anti-TPO) antibodies. A population-based group of 737 women served as controls. Result. The prevalence of thyroid disorders in patients was higher compared to controls [odds ratio (OR) = 2.98, 95% confidence interval (CI) = 1.78-4.99], but the prevalence of subclinical disorders was not different (OR= 1.18, 95% CI = 0.48-2.85). Anti-TPO antibodies were present in 10.6% of MC patients and 18.6% of controls. Twenty-five MC patients had hypothyroidism: 15 with Hashimotos hypothyroidism, 6 with completed treatment of thyrotoxicosis and 4 with completed surgery after nontoxic goiter. Conclusion. Thyroid disorders, autoimmune hypothyroidism being most frequent, are more prevalent in patients with MC than in controls, whereas the prevalence of subclinical thyroid disorders in MC patients does not differ significantly from controls. [ABSTRACT FROM AUTHOR]

Mitochondrial 26-hydroxylation of exogenous cholesterol, endogenous cholesterol, and 5β-cholestane-3α,7α,12α-triol was studied. 26-Hydroxylation of endogenous cholesterol was measured by mass fragmentography. NADPH and isocitrate stimulated 26-hydroxylation of endogenous as well as exogenous cholesterol. 26-Hydroxylation of endogenous cholesterol was linear with time for 15 min, whereas that of exogenous cholesterol was linear with time for at least 40 min. This finding indicates that the fractions of exogenous and endogenous cholesterol that were 26-hydroxylated did not equilibrate. Mg2+ stimulated isocitrate- and NADPH-dependent 26-hydroxylation of exogenous cholesterol but inhibited in the case of endogenous cholesterol. Ca2+ stimulated NADPH-dependent and inhibited isocitrate-dependent 26-hydroxylation of both exogenous and endogenous cholesterol. It is suggested that the differing effect of Mg2+ on the 26-hydroxylation of exogenous and endogenous cholesterol is related to transfer of the steroid to the enzyme. Isocitrate- and NADPH-dependent 26-hydroxylation of exogenous 5β-cholestane-3α,7α,12α-triol differed from that of exogenous cholesterol in response to Mg2+ and Ca2+. 26-Hydroxylation of 5β-cholestane-3α,7α,12α-triol was stimulated by Mg2+ in low concentrations but inhibited by Mg2+ and Ca2+ in high concentrations. Mg2+ had the same influence on the 26-hydroxylation of three dioxygenated C27-steroids known to be intermediates in bile acid biosynthesis. The results are not only compatible with heterogeneity of the mitochondrial 26-hydroxylase system but also with differences in the transport of cholesterol and 5β-cholestane-3α,7α,12α-triol to the enzyme. The finding of a differing effect of Mg2+ on 26-hydroxylation of exogenous and endogenous cholesterol seems to favor differences in transport rather than heterogeneity of the 26-hydroxylase as an explanation of the results.

The effect of biliary obstruction on side chain hydroxylations in the biosynthesis and metabolism of bile acids was studied in the rat. For comparison, several other hydroxylation reactions in bile acid biosynthesis and metabolism were assayed. Biliary obstruction inhibited microsomal 26-hydroxylation of 5β-cholestane-3α,7α-diol and microsomal 25- and 26-hydroxylation of 5β-cholestane-3α,7α-12α-triol. Microsomal 7α-hydroxylation of cholesterol and 6β-hydroxylation of lithocholic acid acid increased significantly, whereas the increase in microsomal 12α-hydroxylation of 5β-cholestane-3α,7α-diol was less. Mitochondrial 26-hydroxylation of cholesterol, 5-cholestene-3β,7α-diol, and 7α-hydroxy-4-cholesten-3-one was stimulated, whereas 26-hydroxylation of 5β-cholestane-3α,7α-diol was not affected and that of 5β-cholestane-3α,7α,12α-triol was markedly inhibited. The results indicate that mitochondrial 26-hydroxylation, particularly of substrates that primarily are precursors of chenodeoxycholic acid, plays a more important role in bile acid biosynthesis under conditions of biliary obstruction than under normal conditions.

The present study was designed to obtain more definitive information in man on the metabolic pathways to chenodeoxycholic acid and to cholic acid via a pathway not involving an initial 7 alpha-hydroxylation of cholesterol. Four bile fistula patients were administered consecutively two or more of the following 3H-labeled bile acid intermediates: 7 alpha-hydroxycholesterol, 7 alpha-hydroxy-4-cholesten-3-one, 5 beta-cholestane 3 alpha,7 alpha,26-triol, 26-hydroxycholesterol,7 alpha,26-dihydroxy-4-cholesten-3-one, and 5-cholestene-3 beta,12 alpha-diol. Both 7 alpha-hydroxy[7 beta-3H]cholesterol and 7 alpha-hydroxy-4-[6 beta-3H]cholesten-3-one were efficiently converted to bile acids and preferred chenodeoxycholic acid over cholic acid. The specific activity time curves indicated that a portion of cholic acid synthesis did not pass through 7 alpha-hydroxycholesterol. [3H]26-Hydroxycholesterol and [3H]-5-cholestene 3 beta,12 alpha-diol, two potential intermediates of this bypass pathway to cholic acid, were poorly converted to primary bile acids (10 to 27%). The [3H]26-hydroxycholesterol preferred chenodeoxycholic over cholic acid by about 4 to 1. The [3H]5-cholestene 3 beta,12 alpha-diol formed cholic acid in low yield (10 to 20%). It is concluded that pathways to primary acids from cholesterol through 26-hydroxycholesterol and 5-cholestene 3 beta,12 alpha-diol are probably of minor quantitative significance. A selective pathway to chenodeoxycholic acid via 26-hydroxylation of 7 alpha-hydroxy-4-cholesten-3-one was also investigated. The 5 beta-cholestane 3 alpha,7 alpha,26-triol was converted in about equal amounts to cholic and chenodeoxycholic acids. The 7 alpha-hydroxy-4-cholesten-3-one was also efficiently converted to both bile acids but preferred chemodeoxycholic acid. The most efficient precursor of chenodeoxycholic acid was 7 alpha,26-dihydroxy-4-cholesten-3-one, which was efficiently converted to primary bile acids; chenodeoxycholic acid was preferred over cholic acid by approximately 7 to 1. These findings suggest the presence of a major pathway to chenodeoxycholic acid via the 26-hydroxylation of 7 alpha-hydroxy-4-cholesten-3-one and intermediate formation of 7 alpha,26-dihydroxy-4-cholesten-3-one.

The metabolism of 3 alpha, 7 alpha-dihydroxy-5 beta-cholestanoic acid was studied in the bile fistula rats and in preparations from rat liver homogenates. In the bile fistula rats, the main products were chenodeoxycholic acid, alpha-muricholic acid, and beta-muricholic acid. Only small amounts of cholic acid were formed. Incubations of 3 alpha, 7 alpha-dihydroxy-5 beta-cholestanoic acid with microsomes and NADPH yielded as the main product 3 alpha, 6 beta, 7 alpha-trihydroxy-5 beta-cholestanoic acid. The formation of small amounts of 3 alpha, 7 alpha, 12 alpha-trihydroxy-5 beta-cholestanoic acid was shown. The major product in incubations of 3 alpha, 7 alpha-dihydroxy-5 beta-cholestanoic acid with microsomes and the 100,000 g supernatant fluid fortified with ATP was identified as 3 alpha, 7 alpha, 24 xi-trihydroxy-5 beta-cholestanoic acid. This compound was converted into chenodeoxycholic acid and its metabolites in the bile fistula rat.

Several hydroxylase activities in bile acid biosynthesis were assayed in subcellular fractions of human fetal liver. The livers were obtained at legal abortions performed between gestational weeks 14 and 24. Microsomal 12 alpha-hydroxylase and mitochondrial 12 alpha- and 26-hydroxylase activities were detected from week 14. The microsomal fraction also had capacity for 25-hydroxylation, whereas 7 alpha- and 26-hydroxylase activities were hardly detectable. The variation of the hydroxylase activities between different experiments can be explained by inactivation during the abortion or workup procedure. The results are discussed with respect to earlier studies of bile acid biosynthesis during development and adult life.