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Distinctive structural differences in the m6A-RNA-binding proteins DF1–DF3 imply functional differences and lay the foundations for paralog-selective drug design. Differences between the DF paralogs in post-translational modifications, and likely also in their conformational states, allostery, and allosteric site cooperativity upon ligand binding, offer further possibilities for paralog-selective inhibition. The DF paralogs have emerged as dynamic scaffold-like proteins which, upon binding to their m6A-mRNA targets, context-dependently bind to other partners such as their effectors. The paralog-selective inhibitors identified so far can be expected to help to further unravel the unique functions of DF paralogs. In turn, increased understanding of the disease-driving functions of the DF paralogs will enable mechanism-based design of more targeted and potent therapeutic inhibitors. Specific RNA sequences modified by a methylated adenosine, N 6-methyladenosine (m6A), contribute to the post-transcriptional regulation of gene expression. The quantity of m6A in RNA is orchestrated by enzymes that write and erase it, while its effects are mediated by proteins that bind to read this modification. Dysfunction of this post-transcriptional regulatory process has been linked to human disease. Although the initial focus has been on pharmacological targeting of the writer and eraser enzymes, interest in the reader proteins has been challenged by a lack of clear understanding of their functional roles and molecular mechanisms of action. Readers of m6A-modified RNA (m6A-RNA) – the YTH (YT521-B homology) domain-containing protein family paralogs 1–3 (YTHDF1–3, referred to here as DF1–DF3) – are emerging as therapeutic targets as their links to pathological processes such as cancer and inflammation and their roles in regulating m6A-RNA fate become clear. We provide an updated understanding of the modes of action of DF1–DF3 and review their structures to unlock insights into drug design approaches for DF paralog-selective inhibition. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • p K a values depend strongly on solvent's acid-base properties and polarity. • Relative p K a values (Δp K a) can often be cross-used between aprotic solvents. • Ion pairing or hydrogen-bonded complexes are important in many solvents. Abstract Acids and bases are ubiquitous. Sometimes, it is essential to know the accurate strength (p K a values) of the acids/bases to work with, but sometimes just acidity/basicity order is enough. We often receive requests to measure p K a values of different substances in different solvents for answering questions like "what acids can be used to protonate this substance" or "what base is able to deprotonate that compound?" Such questions can, in fact, often be answered using published p K a data in different solvents. This digest/tutorial will give an overview of how to make efficient use of the existing p K a data. [ABSTRACT FROM AUTHOR]

• Success of ultrasound-guided perineural injection of the tibial and fibular nerves was not significantly different than blind perineural injection in equine cadaver limbs. • Less diffusion of injectate was observed in the low-volume injection compared to the traditional volume. • Guided perineural injection avoids needle misplacement, increasing the procedure's specificity. • The experience of the veterinarian performing these perineural injections is going to determine the preference between ultrasound-guided or blinded approaches. Techniques for local anesthesia of the tibial (TN) and superficial and deep fibular nerves (FNs) in horses are well established. Ultrasound-guided perineural blocks can identify the nerve location, reduce the anesthetic volume needed and avoid needle misplacement. The aim of this research was to compare the success of blind perineural injection technique (BLIND) to ultrasound-guided technique (USG). Fifteen equine cadaver hindlimbs were divided into two groups. Perineural injection of the TN and FNs was performed using a mixed solution of radiopaque contrast, saline and food dye. BLIND (n = 8) used 15 mL for the TN and 10 mL for each fibular nerve. USG (n = 7) used 3 mL for the TN and 1.5 mL for each fibular nerve. The limbs were radiographed immediately after injections and sectioned transversally to evaluate the diffusion and presence of the injectate adjacent to the TN and FNs. The presence of dye immediately adjacent to the nerves was considered a successful perineural injection. No statistically significant difference was observed between groups for success. Distal diffusion of injectate following perineural injection of the TN was significantly less for USG compared to BLIND. Proximal, distal and medial diffusion of injectate following perineural injection of FNs was significantly less for USG compared to BLIND. Low-volume USG results in less diffusion but similar success compared to BLIND leaving it up to veterinarian preference when selecting a technique. [ABSTRACT FROM AUTHOR]

Twelve novel phosphazene bases (X-C 6 H 4 -N N-C 6 H 4 -N PR 3 ) with an unusual combination of properties – high lipophilicity of both neutral and charged forms, lack of localized charges in the cations, and strong spectral changes upon protonation/deprotonation – were synthesized using the Staudinger reaction and characterized by UV–Vis spectra, p K a values and lipophilicities (log P values). The bases could potentially be useful as working agents in optical sensors and acid-base indicators for lipophilic membranes. [ABSTRACT FROM AUTHOR]

The influence of temperature in a range of 15–5°C, fluctuations in soluble chemical oxygen demand (sCOD) and suspended solids (SS) of the influent and also long hydraulic retention times (HRT) of 36 or 50 d on the performance of a laboratory septic tank were studied. A laboratory-scale septic tank with a volume of 20 L, started up at 15°C was fed with domestic wastewater from two settlements with sCOD up to 450 and up to 2,000 mg/L, respectively. The efficiency of the septic tank was assessed based on pollutant removal and biogas production. A stepwise decrease in temperature by 5°C in the range of 15–5°C halved the daily emission of biogas. Removal efficiencies for sCOD and SS were in the range of 74–86 and 86–88%, respectively. An increase in sCOD of influent from 450 to 4,000 mg/L resulted in a decreased performance of the septic tank (to ~25% less). The highest biogas emission was observed at 10°C and at retention time (36 d), owing to increased consumption of CO2and CH4by autotrophic microorganisms over the longer retention time (50 d). At the 15°C, biogas emission was lower than in case of lower temperatures applied. In the range of 15–5°C, operational temperature did not correlate significantly (p > 0.05) with the removal efficiency of sCOD or SS, assuming as a consequence of the long HRT. [ABSTRACT FROM AUTHOR]

BACKGROUND: Pain is common at an emergency department (ED). Two common scales used to rate intensity are the visual analog scale (VAS) and the numeric rating scale (NRS), but it remains unknown which is superior to use in the ED. AIM: The aim of the study is to compare correlations between values on the VAS and the NRS in patients visiting the ED as well as to assess the patients' preference of scale. METHODS: Patients who visited the ED due to chest pain, abdominal pain, or an orthopedic condition during autumn 2012 were enrolled onto a cross-sectional study with a consecutive sample. Patients rated their pain using the VAS and NRS scales. They answered an open-ended oral questionnaire regarding their preference and their estimation of the sufficiency of the scales. Data were analyzed with significance test. RESULTS: In all, 217 patients (70% of eligible, 94% of invited) participated. The pain scores generated from the NRS and the VAS were found to strongly correlate (mean difference, 0.41; 95% confidence interval, 0.29-0.53). Most patients found the NRS easier to use than the VAS (61% and 22%, respectively; P < .001). Furthermore, a majority reported that the NRS reflected/described their pain better than the VAS (53% and 26%, respectively; P < .01). CONCLUSION: Because values on the NRS correspond well to values on the VAS, values rated with different scales over time might be comparable. Because a majority of the patients found the NRS scale simpler to use and preferred it over the VAS, it might be more appropriate to use in the ED. [ABSTRACT FROM AUTHOR]

The dynamic multiphase flow simulator OLGA [1-4] uses pressure (P), temperature (T), and fluid composition, as independent variables, meaning that all thermodynamic and transport properties for the fluid are given as functions of P and T. Although this is a good approximation for typical multicomponent oil and gas systems, several problems are being faced using the same formulation for pure CO2 and for CO2 containing small amounts of impurities. A better approach is then to use pressure and enthalpy (H) as independent variables for thermodynamic equilibrium calculations and phase properties. This change in formulation is critical for accurate modelling of single component and near single component systems.A prototype P-H formulation has been implemented in OLGA as part of the R&D project CO2-VIP [5].The new calculation scheme is presented here, demonstrated through simple examples, and validated against experimental results. It has proven to give increased simulation accuracy and stability. [ABSTRACT FROM AUTHOR]

While hands-on training is a prerequisite for successful education of nursing students, constraints on clinical training availability and quality have increased focus on effects of in-school simulation training. However, existing research has produced inconsistent conclusions and the literature lacks high-powered evidence from controlled trials. To test effects of a simulation scheme on student professional self-confidence in technical and non-technical skills, as well as to investigate effects on knowledge acquisition and interaction with clinical training. Field experiment, treatment is a three + two day simulation training scheme while control is a standard three hour simulation session. Self-confidence in a list of technical and non-technical skills is measured in three survey-rounds. Enriched with data on type of clinical training site and grade attainment. University College Copenhagen Department of Nursing, all third year students in 2019. 352 in cohort, out of which 316 participated and 311 answered first survey round (163 in treatment, 148 in control). Field experiment analyzed utilizing multivariate OLS regression analysis. Students who receive increased simulation training report markedly higher levels of professional self-confidence immediately after training. This effect is double the size for confidence in technical skills, compared to non-technical skills. The effects on self-confidence in technical skills persist at the end of the following semester for those that receive low intensity clinical training. Students who receive the treatment see a small (and statistically uncertain) relative increase in grade attainment in the semester of treatment, but this difference dissipates over time. Simulation training has substantial positive short-term effects for the professional self-confidence of nursing students and appears to have small positive effects on knowledge acquisition. Most of these effects are crowded out by other factors (notably intensive clinical training) over time but might have long-term positive effects for those that do not receive other intensive hands-on experiences. This is interpreted as an indication that simulation training can be used to compensate for uncertainties in providing sufficient training experiences outside of academic training. [ABSTRACT FROM AUTHOR]

Abstract: In order to functionally characterise the muscarinic vasodilator responses, effects of cholinergic agonists were studied on isolated preparations of the rat submandibular artery and vein and carotid and jugular vessels. Tentatively, a cholinergic regulatory mechanism having different effects on the arterial and venous vessels would enhance vascular fluid recruitment for the secretory response. In vitro functional findings were correlated to the expression and cellular location of the different receptors that were assessed by immunohistochemistry. In order to find in vivo correlates to the in vitro findings, the influence of muscarinic receptors on permeability was studied on the vasculature of the submandibular gland in anaesthetised rats. Staining for muscarinic M1 receptors occurred in the endothelium, and muscarinic M5 receptors, and possibly M3 also, were detected in the arterial smooth muscle. In venous endothelium, muscarinic M1 and M4 receptors occurred. In the jugular smooth muscle layer, staining for M1, and possibly also for M3, appeared. Muscarinic agonists caused arteries to relax and veins to contract. The nitric oxide synthase inhibitor Nω-nitro-l-arginine (l-NNA; 10−4 M) markedly reduced the cholinergic-evoked relaxation of pre-contracted carotid arterial preparations. In the presence of 4-DAMP (10−7 M), the relaxation to cholinergic agonists was inhibited. Pirenzepine (10−5 M) did not only inhibit the relaxatory effects, but even reversed the effects, while it in the jugular vein abolished the cholinergic effects. The arterial nitric oxide-dependent response to muscarinic receptor stimulation consisted of two parts—one sensitive to pirenzepine and 4-DAMP and the other to 4-DAMP only. Inhibition of the former part only, resulted in cholinergic arterial contraction. Also, the submandibular artery and vein responses to muscarinic receptor stimulation show a resemblance with those of the carotid and jugular vessels, i.e. a pronounced arterial relaxation and a contractile component in the venous response. In vivo examination of submandibular glandular vasculature by studying glandular permeability to Evans blue, confirmed the in vitro observations indicating muscarinic M1 receptors preserving perfusion pressure during the secretory process. [Copyright &y& Elsevier]

The emissions of CO2 and H2S from the aqueous solutions and wastewater were studied to determine and compare the times required to reach the equilibrium of H2S and CO2 between water and gas phases. The solutions of NaHCO3 and NaHS were acidified and the change in the pressure of emitted gases was measured with a manometric OxiTop® system. The average time required to achieve the equilibrium state of distribution of CO2 between two phases was 16.7±1.5min, and it did not depend on the initial amount of NaHCO3 in the solution. The average time required to achieve the equilibrium of H2S (sulfide) was 19.5±5.5min, having the same value for solutions with different initial contents of sulfide ions. The average time required to achieve the equilibrium of H2S in the wastewater was 16.2±3.6min, and it showed the faster emission of gaseous H2S to decrease the oversaturation of the solution. The ratio of measured values of pressure to the calculated values did not depend on the concentration of NaHS in the initial solution, and its average value was 0.86±0.14. The results showed that measured values of pressure of H2S emitted from the wastewater were twice lower than the calculated values and it is necessary to take into account the catalyzed formation of polysulfide in the solution of sulfides. [Copyright &y& Elsevier]

Background: Reference standards for resting energy expenditure (REE) are widely used. Current standards are based on measurements made in the first part of the past century in various races and locations. Objective: The aim of the present study was to investigate the application of the World Health Organization (WHO) equations from 1985 in healthy subjects living in a modern, affluent society in Germany and to generate a new formula for predicting REE. Design: The study was a cross-sectional and retrospective analysis of data on REE and body composition obtained from 2528 subjects aged 5-91 y in 7 different centers between 1985 and 2002. Results: MeanREEvaried between 5.63 and 8.07 MJ/d in males and between 5.35 and 6.46 MJ/d in females. WHO prediction equations systematically overestimated REE at low REE values but underestimated REE at high REE values. There were significant and independent effects of sex, age, body mass or fat-free mass, and fat mass on REE. Multivariate regression analysis explained up to 75% of the variance in REE. Two prediction formulas including weight, sex, and age or fat-free mass, fat mass, sex, and age, respectively, were generated in a subpopulation and cross-validated in another subpopulation. Significant deviations were still observed for underweight and normal-weight subjects. REE prediction formulas for specific body mass index groups reduced the deviations. The normative data for REE from the Institute of Medicine underestimated our data by 0.3 MJ/d. Conclusions: REE prediction byWHOformulas systematically overand underestimates REE.REEprediction from a weight group-specific formula is recommended in underweight subjects. [ABSTRACT FROM AUTHOR]

Thirty-eight multiparous Holstein cows were utilized in a completely randomized design to examine the effect of feeding calcium salts of conjugated linoleic acid (CLA) and trans-octadecenoic acids (trans-C[sub18:1]) on animal performance and lipid and glucose metabolism during the transition to lactation. Dietary treatments were initiated approximately 28 d prior to expected calving dates and continued through d 49 postpartum. Prepartum treatments consisted of 1) a basal diet (Control), 2) basal diet + 150 g/d of CLA mix (CLA), and 3) basal diet + 150 g/d of trans-C[sub18:1] mix (TRANS). Amounts of calcium salts of CLA and trans-C[sub18:1] mixes were adjusted to 225 g/d during the 49-d postpartum treatment period. All diets were offered as a total mixed ration. Prepartum fat supplementation had no detectable effects on dry matter intake, body weight, or body condition score. After parturition, cows in the TRANS group consumed less dry matter at wk 4, 5, and 6 of lactation than did cows in the control group. Cows fed the transC[sub18:1] supplement were in a more severe negative energy balance than those fed the control diet at 1 wk of lactation. Periparturient fat supplementation had no detectable effects on milk yield during wk 1 to 7 of lactation. Milk fat was not affected during wk 1 to 4, but was reduced after wk 4 of lactation by dietary CLA. Feeding calcium salts of CLA decreased short- to medium-chain fatty acid (C[sub4] to C[sub14]) concentrations and increased both linoleic and linolenic acid concentrations in milk fat. Concentrations of nonesterified fatty acids and β-hydroxybutyric acid in blood were greater in cows fed the CLA-supplemented diet than in those fed the control diet at 1 wk of lactation. In spite of small numerical tendencies, hepatic lipid and triacylglycerol concentrations did not vary significantly among dietary treatments. Periparturient fat supplementation had no detectable effects on plasma glucose and insulin concentrations.... [ABSTRACT FROM AUTHOR]

Examines the effect of dietary conjugate linoleic acid (CLA) on growth performance and liver composition in broiler chickens. Alteration of hepatic lipid content and fatty acid composition; Increase CLA incorporation into hepatic lipid pools.

Positron emission tomography (PET) is a unique tool for studying regional skeletal muscle glucose metabolsm and blood flow in vivo. The application of PET in the assessment of skeletal muscle glucose metabolism depends on recent improvements in instrumentation, data analysis, and production of 18F-fluorodeoxyglucose (FDG) and 15O water. The data presented support the validity of the 15O water model to measure blood flow and the FDG model for the determination of glucose uptake and glucose kinetic constants (influx, efflux, and phosphorylation) in skeletal muscle. However, quantification of absolute glucose transport and backflux rates should be applied with caution because those calculations are based on unproven assumptions such as validity of the lumped constant for these individual processes and constancy of the free and accessible intracellular glucose pool. It is evident that quantification of glucose fluxes using the triple tracer technology generates conflicting data that violate assumptions inherent in triple tracer or PET modeling. Further FDG-PET studies will have to solve those problems to provide more insight into the regulatory processes of glucose transport and phosphorylation of different insulin-resistant disease states. Promising new areas of PET research will include not only detailed study of glucose kinetics but also the measurement of muscle protein synthesis in vivo, which is of interest in a variety of conditions. [ABSTRACT FROM AUTHOR]

Summary Chemical modifications of RNA provide an additional, epitranscriptomic, level of control over cellular functions. N-6-methylated adenosines (m6As) are found in several types of RNA, and their amounts are regulated by methyltransferases and demethylases. One of the most important enzymes catalyzing generation of m6A on mRNA is the trimer N-6-methyltransferase METTL3-14-WTAP complex. Its activity has been linked to such critical biological processes as cell differentiation, proliferation, and death. We used in silico -based discovery to identify small-molecule ligands that bind to METTL3-14-WTAP and determined experimentally their binding affinity and kinetics, as well as their effect on enzymatic function. We show that these ligands serve as activators of the METTL3-14-WTAP complex. Graphical Abstract Highlights • High-binding-efficiency ligands of METTL3-14-WTAP are identified in silico • The binding mode of compounds overlaps with the METTL3-14-WTAP active site • The compounds are experimentally characterized as METTL3-14-WTAP activators • The compounds affect m6A level in mRNA and rRNA in cells The methyltransferase complex METTL3-14-WTAP catalyzes generation of m6A on mRNA. Selberg et al. report the in silico discovery and experimental characterization of small-molecule compounds with exceptionally high binding efficiencies to METTL3-14-WTAP. Remarkably, these compounds act as enzyme activators and lead to increased m6A levels in RNA. [ABSTRACT FROM AUTHOR]

Highlights • Saline distension improved marginal separation of digital sheath structures on ultrasonographic evaluation. • A closed system (syringe/tubing/needle) prevented air artifact introduction during injection. • Marginal separation was mostly improved for the manica flexoria and deep digital flexor tendon within the sheath. • There was limited improvement in marginal separation of the superficial digital flexor tendon. Abstract Injuries to the structures within the digital flexor tendon sheath (DFTS) can lead to lameness with a variable degree of effusion in horses. In some cases, effusion is absent or minimal, and this may be related to the chronicity and type of injury, or veterinary interventions. The purpose of this study was to determine if saline injection into the DFTS would improve ultrasonographic and magnetic resonance imaging of the distal limb without introducing artifact. Nine normal equine cadaver forelimbs were collected. Non-weight-bearing ultrasonographic and magnetic resonance imaging (MRI) examination of each limb was performed pre- and immediately post-injection of the DFTS. The presence of fluid in the DFTS significantly improved the delineation of the deep digital flexor tendon, manica flexoria, and straight distal sesamoidean ligament visualised using both ultrasonography and MRI (P < 0.05). Significant improvement in visualisation of the margins of the superficial digital flexor tendon was noted only with MRI (P < 0.05). Saline distension did not alter the size/shape of the intra- and extrathecal structures. The findings of this study support further evaluation of this imaging technique in clinical cases with minimal DFTS effusion. [ABSTRACT FROM AUTHOR]

Foot problems are very common causes of lameness in horses. With the recent diagnostic advances to evaluate and treat foot pathology as well as to monitor response to therapy, it is now possible to more accurately evaluate the effectiveness of many of these treatments. This review details some of the recent advances of the most common conservative and surgical treatment options for foot problems in horses, including an overview of evidence on the efficacy to support the use of these treatment options and on factors that may affect prognosis. [ABSTRACT FROM AUTHOR]

Persistence of spatial analyticity is studied for periodic solutions of the dispersion-generalized KdV equation u t − | D x | α u x + u u x = 0 for α ≥ 2 . For a class of analytic initial data with a uniform radius of analyticity σ 0 > 0 , we obtain an asymptotic lower bound σ ( t ) ≥ c t − p on the uniform radius of analyticity σ ( t ) at time t , as t → ∞ , where p = max ( 1 , 4 / α ) . The proof relies on bilinear estimates in Bourgain spaces and an approximate conservation law. [ABSTRACT FROM AUTHOR]

According to current guidelines, hemodynamic status should guide the decision between immediate and delayed coronary angiography (CAG) in out-of-hospital cardiac arrest (OHCA) patients without ST-segment elevation. A delayed strategy is advised in hemodynamically stable patients, and an immediate approach is recommended in unstable patients. This study sought to assess the frequency, predictors, and clinical impact of acute coronary occlusion in hemodynamically stable and unstable OHCA patients without ST-segment elevation. Consecutive unconscious OHCA patients without ST-segment elevation who were undergoing CAG at Bern University Hospital (Bern, Switzerland) between 2011 and 2019 were included. Frequency and predictors of acute coronary artery occlusions and their impact on all-cause and cardiovascular mortality at 1 year were assessed. Among the 386 patients, 169 (43.8%) were hemodynamically stable. Acute coronary occlusions were found in 19.5% of stable and 24.0% of unstable OHCA patients (P = 0.407), and the presence of these occlusions was predicted by initial chest pain and shockable rhythm, but not by hemodynamic status. Acute coronary occlusion was associated with an increased risk of cardiovascular death (adjusted HR: 2.74; 95% CI: 1.22-6.15) but not of all-cause death (adjusted HR: 0.72; 95% CI: 0.44-1.18). Hemodynamic instability was not predictive of fatal outcomes. Acute coronary artery occlusions were found in 1 in 5 OHCA patients without ST-segment elevation. The frequency of these occlusions did not differ between stable and unstable patients, and the occlusions were associated with a higher risk of cardiovascular death. In OHCA patients without ST-segment elevation, chest pain or shockable rhythm rather than hemodynamic status identifies patients with acute coronary occlusion. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: Despite the rapid growth of aortic valve replacement (AVR) for aortic stenosis (AS), limited data suggest symptomatic severe AS remains undertreated.Objectives: This study sought to investigate temporal trends in AVR utilization among patients with a clinical indication for AVR.Methods: Patients with severe AS (aortic valve area <1 cm2) on transthoracic echocardiograms from 2000 to 2017 at 2 large academic medical centers were classified based on clinical guideline indications for AVR and divided into 4 AS subgroups: high gradient with normal left ventricular ejection fraction (LVEF) (HG-NEF), high gradient with low LVEF (HG-LEF), low gradient with normal LVEF (LG-NEF), and low gradient with low LVEF (LG-LEF). Utilization of AVR was examined and predictors identified.Results: Of 10,795 patients, 6,150 (57%) had an indication or potential indication for AVR, of whom 2,977 (48%) received AVR. The frequency of AVR varied by AS subtype with LG groups less likely to receive an AVR (HG-NEF: 70%, HG-LEF: 53%, LG-NEF: 32%, LG-LEF: 38%, P < 0.001). AVR volumes grew over the 18-year study period but were paralleled by comparable growth in the number of patients with an indication for AVR. In patients with a Class I indication, younger age, coronary artery disease, smoking history, higher hematocrit, outpatient index transthoracic echocardiogram, and LVEF ≥0.5 were independently associated with an increased likelihood of receiving an AVR. AVR was associated with improved survival in each AS-subgroup.Conclusions: Over an 18-year period, the proportion of patients with an indication for AVR who did not receive AVR has remained substantial despite the rapid growth of AVR volumes. [ABSTRACT FROM AUTHOR]

Summary: UV–Vis spectroscopy was applied to characterize the nature of dissolved organic matter (DOM) in the inflows and in the outflow of the large and shallow temperate Lake Võrtsjärv and to determine its temporal and spatial dynamics in 2008–2010. The concentration of dissolved organic carbon (DOC) was influenced by water temperature, precipitation, stream gradient, discharge, and percentage of peatland in the catchment area and its mean annual values by rivers varied from 9.2 to 27.7mgL−1. Higher DOC values in the outflow in summer/autumn corresponded to periods of intensive phytoplankton development whereas lower values were observed in winter or early spring when biological processes are at a standstill. The results of specific ultraviolet absorption at 254nm (SUVA254) and 285nm (SUVA285) showed domination of fulvic acids in the rivers. According to our spectroscopic results, the aromaticity of DOM increased with the increasing percentage of peatland and forest and with the decreasing percentage of arable land in the river catchments. [Copyright &y& Elsevier]