Bloch- und Néel-Wände in dünnen ferromagnetischen Schichten

In dünnen ferromagnetischen Schichten erzeugen Domänenwände ein Streufeld. Dies führt dazu, daß die Struktur und Energie solcher Wände gegenüber Wänden im unendlich ausgedehnten Material erheblich beeinflußt werden. NÉEL hat bereits gefunden, daß in dünnen Schichten zwei verschiedene Wandtypen existieren müssen. Das Néelsche Verfahren zur Abschätzung der Streufeldenergie wird in dieser Arbeit durch ein konsequentes Variationsverfahren ersetzt und daraus die Energie und Struktur einer 180°-Wand in einer dünnen Schicht mit einachsiger magnetischer Anisotropie berechnet

Left atrial appendage closure with the Amplatzer™ Cardiac Plug: Rationale for a higher degree of device oversizing at implantation

Background: In left atrial appendage (LAA) closure, the correct sizing of the implantable devices is crucial. Data on the time-dependent changes in the shape and positioning of LAA occlusion devices are missing. We analyzed the results of 33 consecutive patients after implantation of an Amplatzer™ Cardiac Plug (ACP) LAA closure device to get more information on the optimal device sizing during implantation. Methods and results: Thirty-three consecutive patients were enrolled in this observational study. ACP implantation was guided by fluoroscopy and three dimensional transesophageal echocardiography (3-D TEE). Device sizing was based on the largest measured diameter of the intended landing zone adding 2–4 mm of device oversizing. Fluoroscopies were performed at 1 day after, and after 3 months, control 3-D TEE was performed 3 months after implantation. The stability of device positioning and shape was matched with the results of 3-D TEE. Patients’ mean age was 70.2 ± 8 years; mean CHA2DS2VASc score was 3.8 ± 1.1. According to the manufacture’s classification, the post-implant degree of compression of the device-lobe was classified in three categories 1) undercompression “square-like shape” (1 patient); 2) op­timal compression “tire-like shape” (20 patients), 3) overcompression “strawberry-like shape” (12 patients). Changes in the degree of device compression by more than one classification class occurred in 18/33 of our patients. A complete loss of device compression (“square-like shape”) was observed in 9 patients. Despite the changes in device compression, a complete closure of the LAA was achieved in 32/33 patients. Conclusions: There is a temporal change in shape and positioning of the ACP within 3 months after implantation. A late decompression of the ACP lobe was observed in 61% of our patients, leading to a complete loss in device compression in 27%. This observation may be the rationale for a higher degree of ACP oversizing during implantation

Biomedical word sense disambiguation with ontologies and metadata: automation meets accuracy

<p>Abstract</p> <p>Background</p> <p>Ontology term labels can be ambiguous and have multiple senses. While this is no problem for human annotators, it is a challenge to automated methods, which identify ontology terms in text. Classical approaches to word sense disambiguation use co-occurring words or terms. However, most treat ontologies as simple terminologies, without making use of the ontology structure or the semantic similarity between terms. Another useful source of information for disambiguation are metadata. Here, we systematically compare three approaches to word sense disambiguation, which use ontologies and metadata, respectively.</p> <p>Results</p> <p>The 'Closest Sense' method assumes that the ontology defines multiple senses of the term. It computes the shortest path of co-occurring terms in the document to one of these senses. The 'Term Cooc' method defines a log-odds ratio for co-occurring terms including co-occurrences inferred from the ontology structure. The 'MetaData' approach trains a classifier on metadata. It does not require any ontology, but requires training data, which the other methods do not. To evaluate these approaches we defined a manually curated training corpus of 2600 documents for seven ambiguous terms from the Gene Ontology and MeSH. All approaches over all conditions achieve 80% success rate on average. The 'MetaData' approach performed best with 96%, when trained on high-quality data. Its performance deteriorates as quality of the training data decreases. The 'Term Cooc' approach performs better on Gene Ontology (92% success) than on MeSH (73% success) as MeSH is not a strict is-a/part-of, but rather a loose is-related-to hierarchy. The 'Closest Sense' approach achieves on average 80% success rate.</p> <p>Conclusion</p> <p>Metadata is valuable for disambiguation, but requires high quality training data. Closest Sense requires no training, but a large, consistently modelled ontology, which are two opposing conditions. Term Cooc achieves greater 90% success given a consistently modelled ontology. Overall, the results show that well structured ontologies can play a very important role to improve disambiguation.</p> <p>Availability</p> <p>The three benchmark datasets created for the purpose of disambiguation are available in Additional file <supplr sid="S1">1</supplr>.</p> <suppl id="S1"> <title> <p>Additional file 1</p> </title> <text> <p><b>Benchmark datasets used in the experiments.</b> The three corpora (High quality/Low quantity corpus; Medium quality/Medium quantity corpus; Low quality/High quantity corpus) are given in the form of PubMed identifiers (PMID) for True/False cases for the 7 ambiguous terms examined (GO/MeSH/UMLS identifiers are also given).</p> </text> <file name="1471-2105-10-28-S1.txt"> <p>Click here for file</p> </file> </suppl

Exploiting the social and semantic web for guided web archiving

The constantly growing amount of Web content and the success of the Social Web lead to increasing needs for Web archiving. These needs go beyond the pure preservation of Web pages. Web archives are turning into "community memories" that aim at building a better understanding of the public view on, e.g., celebrities, court decisions, and other events. In this paper we present the ARCOMEM architecture that uses semantic information such as entities, topics, and events complemented with information from the social Web to guide a novel Web crawler. The resulting archives are automatically enriched with semantic meta-information to ease the access and allow retrieval based on conditions that involve high-level concepts. The final publication is available at Springer via http://dx.doi.org/10.1007/978-3-642-33290-6_47.German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety/0325296Solland Solar Cells BVSolarWorld Innovations GmbHSCHOTT Solar AGRENA GmbHSINGULUS TECHNOLOGIES A

Fires and forests: A reconstruction of Holocene fire-vegetation relationships in Central Yakutia, Siberia

The year 2021 set new records for wildfire extent in the Republic of Sakha (Yakutia) in eastern Siberia, Russia. Wildfire seasons in this unique region, characterized by its deciduous boreal forest and permafrost landforms, are becoming more intense. Some fires are threatening local communities, while their smoke covers vast stretches of land every summer, posing health risks to people even in the distance. At the same time, the larch trees of the eastern Siberian boreal forest stabilize the permafrost soils below as guardians of a continental-scale storage of terrestrial carbon. It is still largely unknown how the current trend of wildfire intensification will develop in the future, and how it will modify the structure of the boreal forests within the next decades to centuries. However, even though needed for a well-founded evaluation of long-term impacts of changing fire regimes, data on past trends of wildfire activity still remains scarce in eastern Siberia. Here, we present a new reconstruction of boreal fire and vegetation dynamics, spanning the last ca. 10.8 ka. Continuously analyzed macroscopic charcoal particles and a REVEALS-transformed pollen record from a sediment core from Lake Satagay (N 63.078, E 117.998) give insight into long-term trends and relationships between changes in fire regime and vegetation composition and coverage. The data indicates that modern larch-dominated forests co-exist with a lower severity fire regime, whereas early Holocene open larch-birch woodlands enabled increased charcoal accumulation and thus supported a higher severity fire regime. Considering the expected increase in tree mortality caused by wildfires and insect damage, likely to thin out currently denser tree stands, this fire-vegetation relationship suggests a potential upcoming positive feedback on intensifying fire regimes

Perceptions of extended-release buprenorphine injections for opioid use disorder among people who regularly use opioids in Australia

2019 The Authors. Addiction published by John Wiley & Sons Ltd on behalf of Society for the Study of Addiction Aims: To examine perceptions of extended-release (XR) buprenorphine injections among people who regularly use opioids in Australia. Design: Cross-sectional survey prior to implementation. XR-buprenorphine was registered in Australia in November 2018. Setting: Sydney, Melbourne and Hobart. Participants. A total of 402 people who regularly use opioids interviewed December 2017 to March 2018. Measurements: Primary outcome concerned the proportion of participants who believed XR-buprenorphine would be a good treatment option for them, preferred weekly versus monthly injections and perceived advantages/disadvantages of XR-buprenorphine. Independent variables concerned the demographic characteristics and features of current opioid agonist treatment (OAT; medication-type, dose, prescriber/dosing setting, unsupervised doses, out-of-pocket expenses and travel distance). Findings: Sixty-eight per cent [95% confidence interval (CI) = 63-73%] believed XR-buprenorphine was a good treatment option for them. They were more likely to report being younger [26-35 versus \u3e 55 years; odds ratio (OR) = 3.16, 95% CI = 1.12-8.89; P = 0.029], being female (OR = 1.67, 95% CI = 1.04-2.69; P = 0.034), \u3c 10 years school education (OR = 1.87, 95% CI = 1.12-3.12; P = 0.016) and past-month heroin (OR = 1.81, 95% CI = 1.15-2.85; P = 0.006) and methamphetamine use (OR = 1.90, 95% CI = 1.20-3.01; P = 0.006). Fifty-four per cent reported no preference for weekly versus monthly injections, 7% preferred weekly and 39% preferred monthly. Among OAT recipients (n = 255), believing XR-buprenorphine was a good treatment option was associated with shorter treatment episodes (1-2 versus ≥ 2 years; OR = 3.93, 95% CI = 1.26-12.22; P = 0.018), fewer unsupervised doses (≤ 8 doses past-month versus no take-aways; OR = 0.50; 95% CI = 0.27-0.93; P = 0.028) and longer travel distance (≥ 5 versus \u3c 5 km; OR = 2.10, 95% CI = 1.20-3.65; P = 0.009). Sixty-nine per cent reported \u27no problems or concerns\u27 with potential differences in availability, flexibility and location of XR-buprenorphine. Conclusions: Among regular opioid users in Australia, perceptions of extended-release buprenorphine as a good treatment option are associated with being female, recent illicit drug use and factors relating to the (in)convenience of current opioid agonist treatment

A community convention for ecological forecasting: output files and metadata

This document summarizes the open community standards developed by the Ecological Forecasting Initiative (EFI) for the common formatting and archiving of ecological forecasts and the metadata associated with these forecasts. Such open standards are intended to promote interoperability and facilitate forecast adoption, distribution, validation, and synthesis. For output files EFI has adopted a three-tiered approach reflecting trade-offs in forecast data volume and technical expertise. The preferred output file format is netCDF following the Climate and Forecast Convention for dimensions and variable naming, including an ensemble dimension where appropriate. The second-tier option is a semi-long CSV format, with state variables as columns and each row representing a unique issue date time, prediction date time, location, ensemble member, etc. The third-tier option is similar to option 2, but each row represents a specific summary statistic (mean, upper/lower CI) rather than individual ensemble members. For metadata, EFI expands upon the Ecological Metadata Language (EML), using additional Metadata tags to store information designed to facilitate cross-forecast synthesis (e.g. uncertainty propagation, data assimilation, model complexity) and setting a subset of base EML tags (e.g. temporal resolution, output variables) to be required. To facilitate community adoption we also provides a R package containing a number of vignettes on how to both write and read in the EFI standard, as well as a metadata validator tool.First author draf

Evidence for the maintenance of slowly varying equatorial currents by intraseasonal variability

Recent evidence from mooring data in the equatorial Atlantic reveals that semi-annual and longer time scale ocean current variability is close to being resonant with equatorial basin modes. Here we show that intraseasonal variability, with time scales of 10's of days, provides the energy to maintain these resonant basin modes against dissipation. The mechanism is analogous to that by which storm systems in the atmosphere act to maintain the atmospheric jet stream. We demonstrate the mechanism using an idealised model set-up that exhibits equatorial deep jets. The results are supported by direct analysis of available mooring data from the equatorial Atlantic Ocean covering a depth range of several thousand meters. The analysis of the mooring data suggests that the same mechanism also helps maintain the seasonal variability