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The dynamics of the Greenland Ice Sheet are affected by surface meltwater reaching the base of the ice, altering ice contact with the bedrock. Lack of understanding of this evolution hampers the ability to predict the effects of increasing temperatures on the Greenland Ice Sheet mass balance. Here we present a unique high-resolution study of ice velocity response to surface melting based on data from a COSMO-SkyMed satellite campaign over Upernavik Isstrøm (Northwest Greenland) for two months around the end of the 2014 melt season. We show that the velocity variations, due to both short-term (days) and seasonal variations in surface melt rates, are increasing in relative strength farther from the glacier terminus. Furthermore, we observe how ice dynamic response to frontal retreat, reaching several kilometres inland, can obscure the meltwater-induced velocity change close to the terminus. Future studies should consider the flow velocity dependence on the distance to the terminus, and local geometry, to distinguish subglacial hydrologic system changes from frontal processes and local basal conditions.

Phytoalexins are antimicrobial plant metabolites elicited by microbial attack or abiotic stress. We investigated phytoalexin profiles after foliar abiotic elicitation in the crucifer Barbarea vulgaris and interactions with the glucosinolate-myrosinase system. The treatment for abiotic elicitation was a foliar spray with CuCl2 solution, a usual eliciting agent, and three independent experiments were carried out. Two genotypes of B. vulgaris (G-type and P-type) accumulated the same three major phytoalexins in rosette leaves after treatment: phenyl-containing nasturlexin D and indole-containing cyclonasturlexin and cyclobrassinin. Phytoalexin levels were investigated daily by UHPLC-QToF MS and tended to differ among plant types and individual phytoalexins. In roots, phytoalexins were low or not detected. In treated leaves, typical total phytoalexin levels were in the range 1–10 nmol/g fresh wt. during three days after treatment while typical total glucosinolate (GSL) levels were three orders of magnitude higher. Levels of some minor GSLs responded to the treatment: phenethylGSL (PE) and 4-substituted indole GSLs. Levels of PE, a suggested nasturlexin D precursor, were lower in treated plants than controls. Another suggested precursor GSL, 3-hydroxyPE, was not detected, suggesting PE hydrolysis to be a key biosynthetic step. Levels of 4-substituted indole GSLs differed markedly between treated and control plants in most experiments, but not in a consistent way. The dominant GSLs, glucobarbarins, are not believed to be phytoalexin precursors. We observed statistically significant linear correlations between total major phytoalexins and the glucobarbarin products barbarin and resedine, suggesting that GSL turnover for phytoalexin biosynthesis was unspecific. In contrast, we did not find correlations between total major phytoalexins and raphanusamic acid or total glucobarbarins and barbarin. In conclusion, two groups of phytoalexins were detected in B. vulgar

The loss of mass from the Greenland ice sheet causes an increasing influx of freshwater to the Greenlandic fjords and the oceans. Freshwater fluxes from marine-terminating glaciers are important to understand fjord circulation and ecosystem dynamics. Here, we present a data set constructed by reformulating existing products into a shared temporal and spatial framework. We combine three publicly available data sets of solid-ice discharge (iceberg), liquid-surface runoff (runoff) and basal melt to present a cohesive overview of the flow of freshwater from marine-terminating glaciers to the Greenlandic fjords. We also calculate glacier drainage basins and compare our findings to previous studies showing that drainage-basin sizes may vary considerably depending on how they were reconstructed. The data set will be a valuable asset to oceanographic, glaciological and marine biological research activities.

Background: Coarctation of the aorta (CoA), a congenital narrowing of the proximal descending thoracic aorta, is a relatively common form of congenital heart disease. Untreated significant CoA has a major impact on morbidity and mortality. In the past 3 decades, transcatheter intervention (TCI) for CoA has evolved as an alternative to surgery. Objectives: The authors report on all TCIs for CoA performed from 2000 to 2016 in 4 countries covering 25 million inhabitants, with a mean follow-up duration of 6.9 years. Methods: During the study period, 683 interventions were performed on 542 patients. Results: The procedural success rate was 88%, with 9% considered partly successful. Complications at the intervention site occurred in 3.5% of interventions and at the access site in 3.5%. There was no in-hospital mortality. During follow-up, TCI for CoA reduced the presence of hypertension significantly from 73% to 34%, but despite this, many patients remained hypertensive and in need of continuous antihypertensive treatment. Moreover, 8% to 9% of patients needed aortic and/or aortic valve surgery during follow-up. Conclusions: TCI for CoA can be performed with a low risk for complications. Lifetime follow-up after TCI for CoA seems warranted.

We present the Programme for Monitoring of the Greenland Ice Sheet (PROMICE) Ice Velocity product (https://doi.org/10.22008/promice/data/sentinel1icevelocity/greenlandicesheet, Solgaard and Kusk, 2021), which is a time series of Greenland Ice Sheet ice velocity mosaics spanning September 2016 through to the present. The product is based on Sentinel-1 synthetic aperture radar data and has a 500 m grid spacing. A new mosaic is available every 12 d and spans two consecutive Sentinel-1 cycles (24 d). The product is made available within ∼ 10 d of the last acquisition and includes all possible 6 and 12 d pairs within the two Sentinel-1A cycles. We describe our operational processing chain from data selection, mosaicking, and error estimation to final outlier removal. The product is validated against in situ GPS measurements. We find that the standard deviation of the difference between satellite- and GPS-derived velocities (and bias) is 20 m yr−1 (−3 m yr−1) and 27 m yr−1 (−2 m yr−1) for the components in an eastern and northern direction, respectively. Over stable ground the values are 8 m yr−1 (0.1 m yr−1) and 12 m yr−1 (−0.6 m yr−1) in an eastern and northern direction, respectively. This is within the expected values; however, we expect that the GPS measurements carry a considerable part of this uncertainty. We investigate variations in coverage from both a temporal and spatial perspective. The best spatial coverage is achieved in winter due to the comprehensive data coverage by Sentinel-1 and high coherence, while summer mosaics have the lowest coverage due to widespread melt. The southeast Greenland Ice Sheet margin, along with other areas of high accumulation and melt, often has gaps in the ice velocity mosaics. The spatial comprehensiveness and temporal consistency make the product ideal both for monitoring and for studying ice-sheet-wide and glacier-specific ice discharge and

Background: It is well-established that heart failure has a negative impact on quality of life. However, little is known about patient-related predictors of health-related quality of life, anxiety and depression, symptoms and illness perception among patients with heart failure. Aim: To study the association between patient-related predictors and patient-reported outcome measures at discharge from hospital in a cohort of patients with heart failure. Methods: We used data from 1506 patients with heart failure, participating in the national DenHeart Survey of patient-reported outcome measures in patients with heart disease. The potential patient-related predictors included demographic, administrative, clinical and socioeconomic factors. The patient-reported outcome measures included six questionnaires: the Short Form-12, the Hospital Anxiety and Depression Scale, the EuroQol five-dimensional, five-level questionnaire, the HeartQoL, the Brief Illness Perception Questionnaire and the Edmonton Symptom Assessment Scale. Data were linked to national patient registry data and medical records. We performed multivariable linear and logistic regression analyses. Results: In adjusted linear regression analyses we found that a length of hospital stay of >2 days was associated with worse scores across questionnaires, except for the Brief Illness Perception Questionnaire. Higher comorbidity level was associated with worse scores across all questionnaires, whereas low social support was associated with worse scores across questionnaires, except for the physical domain of the Short Form-12 and the HeartQoL global score. Conclusions: This study identified length of hospital stay > 2 days, a higher comorbidity level and low social support to be associated with worse scores across questionnaires at discharge from a cardiac-related hospitalisation in patients with heart failure.

This report contains information on five selected locations that may be utilized for industrial collection of drinking water, and provides the technical background for the second licensing round of the Greenland Government in its Strategy for Export of Ice and Water. This report is not aimed at addressing any technical or engineering questions posed by the locations or water treatment, but only concerns the natural environment and the quality of the water as it was sampled. A prerequisite in the investigation has been that the water should be at least partly derived from meltwater originating either from the Greenland Ice Sheet or from local glaciers and ice caps. The identification and selection process for locations was de-scribed in detail in Ahlstrøm et al. (2018) and updated in Kjeldsen et al. (2019). Locations are defined as outlets of a significant meltwater river to accessible fjords in the southwestern part of Greenland, to minimize potential sea ice and iceberg interference. Catchments for each location or river outlet were derived employing advanced hydrological methods, using the most recent elevation models available. The five selected locations represent different catchment sizes with varying amounts of discharge, ranging from roughly 290,000 million litres per year, down to slightly over 10,000 million litres per year. The rivers at all locations are, on average, discharging water from May to November with the vast majority of water discharging in the period June-September. A comparison between modelled discharge for the catchments for the two periods 1980-1991 and 2006-2017, showed an increase in the discharge at all sites except one, which was stable. A similar method was also used to examine the change in discharge over the last few decades, showing a promising overall melt increase of more than 50 % for the region. The five selected locations were visited by boat to sample the water and collect additional data. The field visits w

The Greenland ice sheet is an excellent observatory for global climate change. Meltwater from the 1.8 million km2 large ice sheet influences oceanic temperature and salinity, nutrient fluxes and global sea level (IPCC 2013). Surface reflectivity is a key driver of surface melt rates (Box et al. 2012). Mapping of different ice-sheet surface types provides a clear indicator of where changes in ice-sheet surface reflectivity are most prominent. Here, we present an updated version of a surface classification algorithm that utilises NASA’s Moderateresolution Imaging Spectroradiometer (MODIS) sensor on the Terra satellite to systematically monitor ice-sheet surface melt (Fausto et al. 2007). Our aim is to determine the areal extent of three surface types over the 2000–2014 period: glacier ice, melting snow (including percolation areas) and dry snow (Cuff ey & Paterson 2010). Monthly 1 km2 resolution surface-type grids can be downloaded via the CryoClim internet portal (www.cryoclim.net). In this report, we briefly describe the updated classification algorithm, validation of surface types and inter-annual variability in surface types., Programme for Monitoring of the Greenland Ice Sheet (PROMICE)

In 2007 the Programme for Monitoring the Greenland Ice Sheet (PROMICE) was initiated to observe and gain insight into the mass budget of Greenland ice masses. By means of in situ observations and remote sensing, PROMICE assesses how much mass is gained as snow accumulation on the surface versus how much is lost by iceberg calving and surface ablation (Ahlstrøm et al. 2008). A key element of PROMICE is a network of automatic weather stations (AWSs) designed to quantify components of the surface mass balance, including the energy exchanges contributing to surface ablation (Van As et al. 2013). The use of these AWS observations is not limited to studies of ice-sheet mass balance. PROMICE contributes to CryoNet (www.globalcryospherewatch.org/cryonet), the core network of surface measurement sites of the World Meteorological Organization (WMO) Global Cryosphere Watch. By real-time delivery through WMO, PROMICE observations contribute to improve both operational forecasting and climate analysis in the data-sparse Arctic. The Greenlandic population, highly dependent on accurate forecasting of weather conditions, benefits directly from these real-time observations. For instance, extreme surface wind speeds are a high-risk element in Greenland. The third-highest wind speed observed at the surface of the Earth (93 m/s or 333 km/h), was recorded in a 8–9 March 1972 storm at Thule in North-West Greenland (Stansfield 1972). In this paper, we discuss the extent to which the Greenland ice sheet generates its own near-surface wind field. We use PROMICE data to gain insight into the interaction between air temperature, radiation and gravity-driven katabatic winds. We focus on a particularly powerful spring storm in 2013 that contributed to a fatality on an ice-sheet ski traverse attempt (Linden 2013)., Programme for Monitoring of the Greenland Ice Sheet (PROMICE)

The Greenland ice sheet is losing mass (Barletta et al. 2012) and at least half of this loss is caused by an increase in surface melt (e.g. Tedesco et al. 2013). The other part is caused by increased dynamic mass loss, as marine-terminating glaciers lose resistive stresses (Nick et al. 2009) due to both retreat and meltwater lubrication at the bed (Sasgen et al. 2012). In 2007, the Programme for Monitoring of the Greenland Ice Sheet (PROMICE) was initiated with the aim of gaining an insight into the causes of the ice-mass budget changes based on quantitative observations. This is primarily done by assessing how much mass is gained as snow accumulation on the surface versus how much is lost by calving and surface ablation (Ahlstrøm et al. 2008). PROMICE monitors the surface mass balance by means of automatic weather stations (AWSs) designed to quantify accumulation and ablation, as well as the specific energy sources contributing to ablation. These observations are vital to interpreting the physical mechanisms for ice-sheet response to climate change and for the calibration and validation of both satellite observations and climate models. In the wake of several record-breaking warm summers – increasing surface melt rate and extent (Nghiem et al. 2012) – interest in Greenland’s surface mass balance has increased (Tedesco et al. 2013). Observations of net ablation at PROMICE stations provided in situ confirmation of extreme massloss events in 2010 (Fausto et al. 2012) and 2012, primarily documented by other workers through satellite data. In this paper, we present atmospheric temperatures and surface solar reflectivity (known as albedo) of the Greenland ice sheet in the PROMICE period. Albedo modulates the absorption of solar radiation, which is the primary source of melt energy. It is reported to be decreasing in Greenland in recent years (Box et al. 2012), causing the monitoring of albedo variability to be increasingly important. Air temperatures, besides being stron, Programme for Monitoring of the Greenland Ice Sheet (PROMICE)

Inodilators are used in the treatment of low cardiac output, mainly after cardiac surgery. At present, there is little knowledge of the effect of inodilators in the newborn heart. Immediately after birth and in the neonatal period, the metabolism and physiology of the heart undergo major changes. We hypothesised that effects of the inodilators milrinone and levosimendan on myocardial contractility and haemodynamics under normal physiological conditions were age dependent. Animal studies were conducted on 48 pigs using a closed-chest biventricular conductance catheter method. Pigs in two age groups, that is, 5-6 days and 5-6 weeks, were assigned to milrinone, levosimendan, or a control group. We observed that both milrinone - 19.2% with a p value of 0.05 - and levosimendan - 25.7% with a p value of 0.03 compared with the control group increased cardiac output, as well as myocardial contractility with a maximum pressure development over time: milrinone 28.2%, p = 0.01 and levosimendan 19.4%, p = 0.05. Milrinone improved diastolic performance (p < 0.05) in the left ventricle in the 5-6-week-old animals. In the newborn animals, neither of the inodilators increased ventricular contractility or cardiac output; however, we observed a significant decrease in the mean arterial pressure: milrinone 34.6%, p < 0.01 and levosimendan 30.1%, p = 0.02. Both inodilators demonstrated age-dependent haemodynamic effects, and it is noteworthy that neither milrinone nor levosimendan was able to increase cardiac output in the newborn heart.

BACKGROUND: Functional health is becoming an important part of outcome assessment following congenital heart surgery.METHODS: The Child Health Questionnaire was used to evaluate self-reported functional health in a cohort of children operated on for congenital heart disease between 1996 and 2002, now aged 10-20 years. A total of 288 schoolchildren served as controls. The association between demographic and clinical factors such as the Risk Adjusted Classification for Congenital Heart Surgery, the Aristotle Basic Complexity Score, physical and psycho-social domains was explored by multivariate analysis.RESULTS: In total 239 children who were operated on (response rate 68%, mean age at assessment 13.1 years, 50% male children) participated. There were no differences between children operated on for congenital heart disease and controls in nine out of thirteen domains. In multivariate analysis, male gender was positively associated with physical, mental and general health. Higher education of the parents was also associated with better scores for family activities, physical, emotional and general health. In contrast, living with a single parent was negatively associated with mental health. Category 4 in the Risk Adjusted Classification for Congenital Heart Surgery was associated with worse scores in all behaviour domains. The Aristotle Basic Complexity Score was not associated with any domain.CONCLUSION: Functional health in children operated for congenital heart disease was overall similar to other children of the same age. Male gender of the child, education of the parents, living with a single parent, and category 4 in the Risk Adjusted Classification for Congenital Heart Surgery were important factors for functional health.

BACKGROUND: Extracardiac total cavo-pulmonary connection (TCPC) bypasses the right atrium and has in theory better hemodynamics than intraatrial TCPC repair. Both are thought to have inferior hemodynamics compared with a normal circulation. Direct comparison of flow rates at rest and during exercise with magnetic resonance imaging technique have not been performed.METHODS: The study comprised 20 children. Six children (median age, 9.3 years; interquartile range, 2.2) had undergone extracardiac TCPC. Eight children (median age, 8.9 years; interquartile range, 5.0) had an intraatrial TCPC, and 6 children (median age, 10.3 years; interquartile range, 2.6) were healthy control subjects. Blood flows in the aorta, inferior vena cava, and superior vena cava were measured at rest and during two levels of submaximal supine bicycle exercise (0.5 W/kg and 1.0 W/kg) using a magnetic resonance imaging scanner mounted with a bicycle.RESULTS: Heart rate, respiratory rate, inspiratory fraction, and blood flow rates in the aorta and inferior vena cava increased equally in all three groups. If patients were grouped together, flow rates were significantly lower, and the inspiratory flow fraction in the inferior vena cava was significantly higher, than in control subjects. Retrograde flows were observed in all three groups at rest but tapered off with exercise.CONCLUSIONS: At submaximal levels of lower limb exercise, patients with extracardiac as well as intraatrial TCPC showed a similar increase in respiration, heart rate, and aortic and caval flow rates as healthy control subjects. This is in accordance with the observation that many patients with TCPC perform well during daily life activities.