Although microRNAs are supposed to be stable in-vivo, degradation processes potentially blur our knowledge on the small oligonucleotides. We set to quantify the effect of degradation on microRNAs in ...mouse to identify causes for distorted microRNAs patterns. In liver, we found 298, 99 and 8 microRNAs whose expression significantly correlated to RNA integrity, storage time at room temperature and storage time at 4 °C, respectively. Expression levels of 226 microRNAs significantly differed between liver samples with high RNA integrity compared to liver samples with low RNA integrity by more than two-fold. Especially the 157 microRNAs with increased expression in tissue samples with low RNA integrity were most recently added to miRBase. Testing potentially confounding sources, e.g. in-vitro degraded RNA depleted of small RNAs, we detected signals for 350 microRNAs, suggesting cross-hybridization of fragmented RNAs. Therefore, we conclude that especially microRNAs added in the latest miRBase versions might be artefacts due to RNA degradation. The results facilitate differentiation between degradation-resilient microRNAs, degradation-sensitive microRNAs, and likely erroneously annotated microRNAs. The latter were largely identified by NGS but not experimentally validated and can severely bias microRNA biomarker research and impact the value of microRNAs as diagnostic, prognostic or therapeutic tools.
For segmenting complex structures like vertebrae, a priori knowledge by means of statistical shape models (SSMs) is often incorporated. One of the main challenges using SSMs is the solution of the ...correspondence problem. In this work we present a generic automated approach for solving the correspondence problem for vertebrae. We determine two closed loops on a reference shape and propagate them consistently to the remaining shapes of the training set. Then every shape is cut along these loops and parameterized to a rectangle. There, we optimize a novel combined energy to establish the correspondences and to reduce the unavoidable area and angle distortion. Finally, we present an adaptive resampling method to achieve a good shape representation. A qualitative and quantitative evaluation shows that using our method we can generate SSMs of higher quality than the ICP approach.
Das intuitiv empfundene Beziehungsgeflecht der Künste interessiert Menschen seit jeher. Sich diesem zu nähern bedeutet, allgemeine übergeordnete Strukturen zu ermitteln. E.T.A. Hoffmann und Robert ...Schumann schufen zwei gleichnamige Werke, die »Kreisleriana«. Den hier implizierten Verweis auf enge Bezüge zwischen Literatur und Musik nimmt die Studie zum Anlass, romantische Universalpoesie mit strukturalistischen Mythenkonzepten sowie der platonischen Idee einer chora in Konflikt zu setzen und auf den gattungstranszendierenden Vergleich zu erweitern. Diese originelle Vernetzung unterschiedlicher Modelle ermöglicht Einsicht in die fundamentalästhetischen Strukturen von Kunstwerken.
ICOS-Oceans is the marine domain of the European Research Infrastructure Consortium “Integrated Carbon Observation System” (ICOS). It aims at delivering high quality greenhouse gas (GHG) observations ...and derived data products (e.g. regional GHG-flux maps) for constraining the GHG balance on a European level, on a sustained long-term basis. ICOS-Oceans currently consists of 11 Ship of Opportunity lines (SOOP – Ship of Opportunity Program) and 10 Fixed Observation Stations (FOS) spread across European waters, including the North Atlantic Ocean and the Barents, North, Baltic and Mediterranean Seas. The stations operate in a harmonised and standardised way based on community-proven protocols and methods for ocean GHG observations improving operational conformity as well as quality control and assurance of the data. This enables the network to focus on long term research into the marine carbon cycle and the anthropogenic carbon sink, while preparing the network to include other GHG fluxes. ICOS data are processed on a near real-time basis and will be published on the ICOS Carbon Portal, allowing monthly estimates of CO2 air-sea exchange to be quantified for European waters. ICOS establishes transparent operational data management routines following the FAIR (Findable, Accessible, Interoperable and Reusable) guiding principles allowing amongst others reproducibility, interoperability and traceability. The ICOS-Oceans network is actively integrating with the atmospheric (e.g. improved atmospheric measurements onboard SOOP lines) and ecosystem (e.g. oceanic direct gas flux measurements) domains of ICOS, and utilises techniques developed by the ICOS Central Facilities and the Carbon Portal. There is a strong interaction with the international ocean carbon cycle community to enhance interoperability and harmonise data flow. The future vision of ICOS-Oceans includes ship-based ocean survey sections to obtain a 3-dimensional understanding of marine carbon cycle processes and optimise the existing network design.
We sought to determine the diagnostic performance of the new high-sensitivity cardiac troponin T (hs-cTnT) assay for early detection of non-ST-segment myocardial infarction (NSTEMI) in patients with ...acute coronary syndrome.
We enrolled patients with retrospectively confirmed unstable angina or NSTEMI and an initially negative cTnT concentration and compared the performance of baseline concentrations and serial changes in concentration within 3 and 6 h. Percentage change criteria included >or=20% delta change and ROC-optimized value.
Based on the standard fourth-generation cTnT result of >or=0.03 microg/L, an evolving NSTEMI was diagnosed in 26 patients, and 31 patients were classified as having unstable angina. With the use of the hs-cTnT assay at the 99th-percentile cutoff, the percentage of NSTEMI cases detected increased gradually from 61.5% on presentation to 100% within 6 h, and the overall number of MI diagnoses increased by 34.6% (35 vs 26 cases). A delta change >or=20% or >or=ROC-optimized value of >117% within 3 h or >or=243% within 6 h yielded a specificity of 100% at sensitivities between 69% and 76%. The standard cTnT at the 99th percentile was less sensitive than hs-cTnT for early diagnosis of MI on presentation, and follow-up samples obtained within the initial 3 h demonstrated very low specificity of cTnT compared with hs-cTnT.
The high-sensitivity cTnT assay increases the number of NSTEMI diagnoses and enables earlier detection of evolving NSTEMI. A doubling of the hs-cTnT concentration within 3 h in the presence of a second concentration >or=99th percentile is associated with a positive predictive value of 100% and a negative predictive value of 88%.
Ships of opportunity are a frequently used platform in surface ocean carbon observations and estimating the annual ocean carbon sink. For understanding the drivers behind changes in the ocean carbon ...system, oxygen measurements alongside the carbon dioxide measurements can be a valuable tool. We developed an in‐air calibration system for oxygen optodes in underway systems. The regular measurements of atmospheric oxygen enable us to correct for sensor drift and biofouling. This new system can help to obtain reliable oxygen data from underway applications, especially if the vessel is not easily accessible and a frequent recalibration of the optode is not feasible.
•We show strong increasing trends in the seasonal surface water fCO2 in the northern Barents Sea and Nansen Basin.•The strong trends are correlated to a sharp decline in sea ice ...concentration.•Increases in salinity, reflecting an Atlantification of the area, contribute to the strong trends in the surface water fCO2.
Maps of surface water fugacity of CO2 (fCO2) over eastern Fram Strait, south-western Nansen Basin, and the north-western Barents Sea (73–84°N, 5–46°E) from September 1997 to December 2020 were made and used to investigate seasonal and temporal trends. The mapping utilized a neural network technique, the self-organizing map (SOM), that was trained with different combinations of satellite/observational/model data of sea surface temperature (SST), sea surface salinity (SSS), mixed layer depth (MLD), chlorophyll a (Chl a), sea ice concentration, and atmospheric mole fraction of CO2 (xCO2). The trained SOM was labelled with available surface ocean fCO2 data, and the labelled SOM was subsequently used to map the fCO2. The produced maps reveal that fCO2 in northern Barents Sea, at the border of the Nansen Basin, has increased significantly over the last decades by between 4.2 and 5.5 ± 0.6–1.1 µatm yr−1 over the winter to summer seasons. These rates are twice the rate of atmospheric CO2 increase, which was about 2 µatm yr−1. The spatial pattern coincides with the strongest decreases in sea ice concentration as well as with a salinification of the surface water. The former allows for a prolongation of the air-sea CO2 flux with resultant oceanic CO2 uptake in previously ice-covered waters, and the latter is caused by a shift from Arctic Water dominance to more saline waters containing more dissolved inorganic carbon, most likely of Atlantic Water origin although brine-release influenced deep water may also contribute.
The North Atlantic Ocean plays a major role in climate change not the least due to its importance in CO2 uptake and thus natural carbon sequestration. The CO2 concentration in its surface waters, ...which determines the ocean's CO2 sink/source function, varies on seasonal and interannual time scales and is mainly driven by air‐sea gas exchange, temperature variability, and biological production/respiration. The variability in stable carbon isotope signatures can provide further insight and help to improve the understanding of the controls of the surface ocean carbon system. In this work, a cavity ringdown spectrometer was coupled to a classical, equilibrator‐based pCO2 system on a voluntary observing ship line that regularly sails across the subpolar North Atlantic between North America and Europe. From 2012 to 2014, a 3‐year time series of underway surface δ13C(CO2) data was obtained along with continuous measurements of temperature, salinity, and fCO2. We perform a decomposition of thermal and nonthermal drivers of fCO2 and δ13C(CO2). The direct measurement of the surface ocean δ13C(CO2) allows us to estimate the mass flux and also the stable carbon isotope fractionation during air‐sea gas exchange. While the CO2 mass flow was in the range of 1–2 mol CO2·m−2·year−1 on the shelves and 2.5–3.5 mol CO2·m−2·year−1 in the open ocean, the isotope signature of this CO2 flux with respect to the sea surface ranged from −2.6 ± 1.4‰ on the shelves to −6.6 ± 0.9‰ in the western and −4.5 ± 0.9‰ in the eastern part of the open ocean section.
Key Points
Three years of continuous underway measurements of stable carbon isotopes in sea surface CO2 were performed in the North Atlantic Ocean
A cavity ringdown spectrometer was successfully implemented and operated autonomously on a commercial vessel
The isotope signature of air‐sea gas exchange was determined
The Active Shape Model (ASM) is a segmentation algorithm which uses a Statistical Shape Model (SSM) to constrain segmentations to ‘plausible’ shapes. This makes it possible to robustly segment organs ...with low contrast to adjacent structures. The standard SSM assumes that shapes are Gaussian distributed, which implies that unseen shapes can be expressed by linear combinations of the training shapes. Although this assumption does not always hold true, and several nonlinear SSMs have been proposed in the literature, virtually all applications in medical imaging use the linear SSM. In this work, we investigate 3D ASM segmentation with a nonlinear SSM based on Kernel PCA. We show that a recently published energy minimization approach for constraining shapes with a linear shape model extends to the nonlinear case, and overcomes shortcomings of previously published approaches. Our approach for nonlinear ASM segmentation is applied to vertebra segmentation and evaluated against the linear model.
We developed a simple method to refine existing open-ocean maps and extend them towards different coastal seas. Using a multi-linear regression
we produced monthly maps of surface ocean fCO2 in the ...northern European coastal seas (the North Sea, the Baltic Sea, the Norwegian Coast and the
Barents Sea) covering a time period from 1998 to 2016. A comparison with gridded Surface Ocean
CO2 Atlas (SOCAT) v5 data revealed mean biases and standard deviations of
0 ± 26 µatm in the North Sea, 0 ± 16 µatm along the Norwegian Coast, 0 ± 19 µatm in the
Barents Sea and 2 ± 42 µatm in the Baltic Sea. We used these maps to investigate trends in fCO2, pH and air–sea
CO2 flux. The surface ocean fCO2 trends are smaller than the atmospheric trend in most of the studied regions. The only
exception to this is the western part of the North Sea, where sea surface fCO2 increases by 2 µatm yr−1, which is similar
to the atmospheric trend. The Baltic Sea does not show a significant trend. Here, the variability was much larger than the expected
trends. Consistently, the pH trends were smaller than expected for an increase in fCO2 in pace with the rise of atmospheric
CO2 levels. The calculated air–sea CO2 fluxes revealed that most regions were net sinks for CO2. Only the southern
North Sea and the Baltic Sea emitted CO2 to the atmosphere. Especially in the northern regions the sink strength increased during the
studied period.
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