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Inland waters, such as lakes, reservoirs and rivers, are important sources of climate forcing trace gases. A key parameter that regulates the gas exchange between water and the atmosphere is the gas transfer velocity, which itself is controlled by near‐surface turbulence in the water. While in lakes and reservoirs, near‐surface turbulence is mainly driven by atmospheric forcing, in shallow rivers and streams it is generated by bottom friction of gravity‐forced flow. Large rivers represent a transition between these two cases. Near‐surface turbulence has rarely been measured in rivers and the drivers of turbulence have not been quantified. We analyzed continuous measurements of flow velocity and quantified turbulence as the rate of dissipation of turbulent kinetic energy over the ice‐free season in a large regulated river in Northern Finland. Measured dissipation rates agreed with predictions from bulk parameters, including mean flow velocity, wind speed, surface heat flux, and with a one‐dimensional numerical turbulence model. Values ranged from ∼10−10m2s−3 to 10−5m2s−3. Atmospheric forcing or gravity was the dominant driver of near‐surface turbulence for similar fraction of the time. Large variability in near‐surface dissipation rate occurred at diel time scales, when the flow velocity was strongly affected by downstream dam operation. By combining scaling relations for boundary‐layer turbulence at the river bed and at the air‐water interface, we derived a simple model for estimating the relative contributions of wind speed and bottom friction of river flow as a function of depth. Plain Language Summary: Inland water bodies such as lakes, reservoirs and rivers are an important source of climate forcing trace gases to the atmosphere. Gas exchange between water and the atmosphere is regulated by the gas transfer velocity and the concentration difference between the water surface and the atmosphere. The gas transfer velocity depends on near‐surface turbulence, but robust formulations have not been developed for river systems. Their surface area is sufficiently large for meteorological forcing to cause turbulence, as in lakes and reservoirs, but turbulence generated from bed and internal friction of gravity‐driven flows is also expected to contribute. Here we quantify near‐surface turbulence using data from continuous air and water side measurements conducted over the ice‐free season in a large subarctic regulated river in Finland. We find that turbulence, quantified as the dissipation rate of turbulent kinetic energy, is well described using equations for predicting turbulence from meteorological data for sufficiently high wind speeds whereas the contribution from bottom shear dominated at higher flow velocities. A one‐dimensional river model successfully captured these processes. We provide a fundamental model for estimating the relative contributions of atmospheric forcing and bottom friction as a function of depth. Key Points: Wind and river flow make comparable contributions to near‐surface turbulence in a regulated riverDissipation rates predicted from wind speed and flow velocity are in good agreement with observationsDiel variability in dissipation rates occurs in response to flow regulation and atmospheric forcing [ABSTRACT FROM AUTHOR]

After a rather turbulent taxonomic history, Dysphanieae (Chenopodioideae, Amaranthaceae) were established to contain five genera, four of which are monospecific (Cycloloma, Neomonolepis, Suckleya, Teloxys) and geographically restricted, and the fifth genus, Dysphania, having a nearly worldwide distribution and comprising ca. 50 species. This study investigates the phylogeny, biogeography and taxonomy of Dysphanieae. We studied specimens from 32 herbaria to infer morphological differences and distribution areas of the species and sampled 121 accessions representing 39 accepted species of the tribe for molecular phylogenetic analyses. The molecular phylogeny tested generic relationships of the tribe and infrageneric relationships of Dysphania on the basis of two plastid DNA markers (atpB‐rbcL spacer, rpl16 intron) and two nuclear ribosomal markers (ETS, ITS) and was also used for an ancestral area reconstruction with BioGeoBEARS. Three of the monospecific genera (Neomonolepis, Suckleya, Teloxys) form a basal grade and appear to be relictual lineages of the tribe, while Cycloloma is nested within Dysphania. The ancestral area reconstruction favors a widespread ancestry for Dysphanieae, and the relictual lineages in Asia (Teloxys) and North America (Neomonolepis, Suckleya) might be explained by a wide distribution across Beringia during the Late Oligocene/Early Miocene. Dysphania likely originated in North America; however, the simultaneous diversification into three major clades, an Asian/African, an American and an Australian/African clade, indicates a widespread ancestor at the crown node of Dysphania. Our taxonomic revision results in four accepted genera in Dysphanieae, Dysphania, Neomonolepis, Suckleya and Teloxys. The sectional subdivision for Dysphania is revised. We subdivide the genus into five sections, D. sect. Adenois (13 spp.), D. sect. Botryoides (10 spp.), D. sect. Dysphania (17 spp.), D. sect. Incisa (2 spp.) and D. sect. Margaritaria (4 spp.); three strongly deviating species remain unplaced and need further attention. [ABSTRACT FROM AUTHOR]

We report an increase in winter (DJF) cyclone densities in the areas around Svalbard and in northwestern Barents Sea and a decrease in cyclone densities in southeastern Barents Sea during 1979–2016. Despite high interannual variability, the trends are significant at the 90% confidence level. The changes appear as a result of a shift into a more meridional winter storm track in the high‐latitude North Atlantic, associated with a positive trend in the Scandinavian Pattern. A significant decrease in the Brunt–Väisälä frequency east of Svalbard and a significant increase in the Eady Growth Rate north of Svalbard indicate increased baroclinicity, favouring enhanced cyclone activity in these regions. For the first time, we apply composite analysis to explicitly address regional consequences of these wintertime changes in the high‐latitude North Atlantic. We find a tendency toward a warmer and more moist atmospheric state in the Barents Sea and over Svalbard with increased cyclone activity around Svalbard. [ABSTRACT FROM AUTHOR]

Surface layer and upper‐air in situ observations from two research vessel cruises and an ice station in the Weddell Sea from 1992 and 1996 are used to validate four current atmospheric reanalysis products: ERA‐Interim, CFSR, JRA‐55, and MERRA‐2. Three of the observation data sets were not available for assimilation, providing a rare opportunity to validate the reanalyses in the otherwise datasparse region of the Antarctic against independent data. All four reanalyses produce 2 m temperatures warmer than the observations, and the biases vary from +2.0 K in CFSR to +2.8 K in MERRA‐2. All four reanalyses are generally too warm also higher up in the atmospheric boundary layer (ABL), with biases up to +1.4 K (ERA‐Interim). Cloud fractions are relatively poorly reproduced by the reanalyses, MERRA‐2 and JRA‐55 having the strongest positive and negative biases of about +30 % and −17 %, respectively. Skill scores of the error statistics reveal that ERA‐Interim compares generally the most favorably against both the surface layer and the upper‐air observations. CFSR compares the second best and JRA‐55 and MERRA‐2 have the least favorable scores. The ABL warm bias is consistent with previous evaluation studies in high latitudes, where more recent observations have been applied. As the amount of observations has varied depending on the decade, season, and region, the consistency of the warm bias suggests a need to improve the modeling systems, including data assimilation as well as ABL and surface parameterizations. Plain Language Summary: Surface layer and upper‐air in situ observations from two research vessel cruises and an ice station in the Weddell Sea from 1992 and 1996 are used to validate four atmospheric reanalyses products. Three of the observation data sets were not available in compiling the reanalyses. This provides a rare opportunity to validate the reanalyses in the otherwise datasparse region of the Antarctic against independent data. The reanalyses differ in performance. However, all four reanalyses have large errors in the cloud cover, and they also generally display too high temperatures in the lowermost part of the atmosphere. The latter finding is consistent with previous validation studies in polar regions, in which more recent observations have been applied. As the amount of observations has varied depending on the decade, season, and region, the consistency of the warm bias suggests a need to improve the representation of physical processes in the lowest parts of the atmosphere in the reanalyses investigated. Key Points: ERA Interim and CFSR performed best for meteorological variables and downward radiationAll four reanalyses assessed are generally too warm in the boundary layerThe consistency of the ABL warm bias over decades calls for improvement of ABL parameterizations [ABSTRACT FROM AUTHOR]

Aim To identify floristic elements in the European flora by an analysis of the distributions of species and species groups mapped in Atlas Florae Europaeae. Location Europe, as defined by Flora Europaea. Methods We analysed the native distributions of 2762 species and 33 species’ aggregates from 79 families, which represent c. 20% of the European flora. The distributional data base, derived from Atlas Florae Europaeae, includes records from 4420 50 × 50-km UTM grid squares. We classified species into floristic elements by a three-stage clustering procedure, which consisted of: (1) constructing a dissimilarity hierarchy by complete linkage clustering, using a distance measure based on Jaccard’s coefficient; (2) cutting the hierarchical tree at the 0.95 level to create initial clusters, and forcing small clusters to link with larger ones until the sum of within-group pairwise distances exceeded a threshold value; and (3) checking the allocation of all species to the redefined clusters and reassigning species if appropriate, using the cosine of the angle between the species and cluster centres to measure the similarity of species to clusters. Results The clustering procedure classified 2793 taxa into 18 floristic elements, which included between 66 and 289 taxa; two species had unique, non-overlapping distributions and could not be classified. Main conclusions The analysis highlights the floristic diversity of the mountains of central and southern Europe, and of the Mediterranean region. The floristic elements of northern latitudes and the temperate lowlands tend to be composed of wide-ranging species and include only a low proportion of European endemics. The montane elements, including those centred on montane areas in the Mediterranean region, are composed predominantly of perennial species and include high or very high proportions of European endemics. Classifications that recognize one ‘Alpine’ and one ‘Mediterranean’ biogeographical zone in Europe fail to reflect this floristic diversity. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the effect of medroxyprogesterone acetate (MPA) therapy on pulmonary arterial pressure (PAP), exhaled nitric oxide (NO), electrocardiogram (ECG), and on arterial blood gases (ABG).Design: A double-blind randomized placebo-controlled cross-over trial.Setting: University hospital in Turku, Finland.Subjects: Fourteen postmenopausal women with respiratory impairment.Interventions: A 2-week placebo and a 2-week MPA period (60 mg day -1) followed by 6-week placebo or MPA washout periods.Main Outcome Measures: The systolic PAP was estimated by Doppler echocardiography. PAP, ECG, NO and ABG were monitored at baseline, after 2-week placebo and MPA periods, and after 3- and 6-week placebo and MPA washout periods.Results: The mean PaCO2 at baseline was 5.4 +/- 0.6 kPa (mean +/- SD). The average decrease of PaCO2 on MPA was -0.8 +/- 0.3 kPa (P < 0.001) and 0.3 +/- 1.0 kPa (P = 0.007) at the 3-week washout. The mean systolic PAP at baseline was 44.3 +/- 14.5 mm Hg. MPA did not change PAP until the 6-week washout, when the average increase of + 6.9 +/- 19.8 mm Hg (P = 0.002) was observed. No changes occurred in PaO2, exhaled NO or the ECG axes. The PR interval was shorter only on MPA (15.9 +/- 27.0 ms, P = 0.020) whereas the QRS duration remained shorter up to 3-week washout (3.9 +/0 5.5 ms, P = 0.008 and 4.0 +/- 14.3 ms, P = 0.032). The systolic and diastolic BP and the heart rate did not change.Conclusions: Despite prolonged decrease in PaCO2, short-term MPA had no effect on exhaled NO and did not decrease systolic PAP in postmenopausal women with respiratory impairment. MPA shortened the PR interval and the QRS duration, the latter effect being sustained at least up to 3 weeks. [ABSTRACT FROM AUTHOR]

Background: Perioperative myocardial ischaemia is an important risk factor for cardiac morbidity and mortality after noncardiac surgery. The impact of analgesic management on the incidence and severity of cardiac ischemia was studied in 77 elderly patients undergoing surgical treatment of traumatic hip fracture. Methods: After hospital admission and written consent, patients were randomised to conventional analgesic regimen (intramuscular oxycodone, OPI group) or continuous epidural infusion of bupivacaine/fentanyl (EPI group). The analgesic regimens were started preoperatively. Patients were operated under spinal anaesthesia and the treatments were continued three days postoperatively. ECG was continuously recorded. ST segment depression of ≥0.1 mV or elevation of ≥0.2 mV lasting ≥1 min were considered as ischaemic episodes. Nocturnal arterial oxygen saturation (SaO2) was recorded perioperatively, and subjective pain was assessed every morning using a visual analogue scale (VAS). Results: Fifty-nine (OPI 30, EPI 29) patients were evaluable for efficacy. Thirteen patients (43%) in the OPI and 12 patients (41%) in the EPI group had ischaemic episodes (NS). However, significantly more patients in the OPI group had ischaemic episodes during the surgery (8 vs. 0 in the EPI group, P=0.005). The median (quartal deviation) total ischaemic burden (i.e. integral of ST-change vs. time) in patients with ischaemic episodes was ten times larger in the OPI group (340 [342] mm · min) compared with the EPI group (30 [36] mm · min) (P=0.002). There were no significant differences between the groups in average heart rates or in heart rates at the start of ischaemic episodes or in maximal heart rates during the attacks. Average nocturnal SaO2 was similar in the two groups and there were no differences in the number of hypoxaemic (SaO2<90%) episodes. Preoperatively there were no differences in subjective pain, but postoperative and average perioperative VAS scores for pain were almost 40% lower in the EPI group (P=0.006). Perioperative myocardial infarctions were not detected. Conclusions: Continuous epidural bupivacaine/fentanyl analgesic regimen, started preoperatively, reduces the amount of myocardial ischaemia in elderly patients with hip fracture. [ABSTRACT FROM AUTHOR]