67 research outputs found
Metric-based Selection of Timer Methods for Accurate Measurements
ABSTRACT Performance measurements are often concerned with accurate recording of timing values, which requires timer methods of high quality. Evaluating the quality of a given timer method or performance counter involves analysing several properties, such as accuracy, invocation cost and timer stability. These properties are metrics with platform-dependent values, and ranking and selecting timer methods requires comparisons using multidimensional metric sets, which make the comparisons ambiguous and unnecessary complex. To solve this problem, this paper proposes a new unified metric that allows for a simpler comparison. The one-dimensional metric is designed to capture fine-granular differences between timer methods, and normalises accuracy and other quality attributes by using CPU cycles instead of time units. The proposed metric is evaluated on all timer methods provided by Java and .NET platform APIs
Tiny wasps, huge diversity – A review of German Pteromalidae with new generic and species records (Hymenoptera: Chalcidoidea)
Despite their ecological and economic importance, hymenopteran parasitoids are severely understudied. Even in countries with a long taxonomic history such as Germany, dating back to the 18th century and including prolific figures like Christian Gottfired Nees von Esenbeck and Otto Schmiedeknecht, those species-rich groups are seldom the subject of comprehensive research efforts, leaving their true diversity unknown. This is often due to their small size of a few millimetres on average, leading to difficulties in their identification and examination. The chalcidoid family Pteromalidae is no exception to this neglect. So far, 735 species have been reported from Germany. Estimating the diversity of this group is not possible, but it has to be assumed that many more species are still to be discovered in Germany.With this study, we improve the knowledge on pteromalid diversity and present new records of 17 genera and 41 species, previously unknown to occur in Germany. We also match and describe previously unknown sexes of two species, based on DNA barcode data. The results of this study were generated as part of the German Barcode of Life Project. The newly-recorded species are illustrated and notes on the biology and distribution are given. The ecological significance of Pteromalidae and potential value as indicators for nature conservation efforts are briefly discussed
High Frequency Trading - Costs and Benefits in Securities Trading and its Necessity of Regulations
The Crystal Structure of a Cyanobacterial Water-Soluble Carotenoid Binding Protein
AbstractCarotenoids undergo a wide range of photochemical reactions in animal, plant, and microbial systems. In photosynthetic organisms, in addition to light harvesting, they perform an essential role in protecting against light-induced damage by quenching singlet oxygen, superoxide anion radicals, or triplet-state chlorophyll. We have determined the crystal structure of a water-soluble orange carotenoid protein (OCP) isolated from the cyanobacterium Arthrospira maxima at a resolution of 2.1 Å. OCP forms a homodimer with one carotenoid molecule per monomer. The carotenoid binding site is lined by a striking number of methionine residues. The structure reveals several possible ways in which the protein environment influences the spectral properties of the pigment and provides insight into how the OCP carries out its putative functions in photoprotection
Cyclurban - A lessons learned report
The lessons learned report summarizes the findings of the project „Cycling as an element of urban climate mitigation policy (Cyclurban)”. The project advance cycling as a measure for sustainable urban mobility and climate mitigation on a local level. In particular, the project researched the situation and developed measures to strengthen cycling mobility in the areas infrastructure, policy and planning, services and promotion, also taking into account new developments such as e-bikes and cargo bikes. The project consortium covered seven EU countries (Germany, Estonia, Latvia, Poland, Croatia, Greece, Slovakia). The report is available in seven languages
Percutaneous dilatational tracheotomy in high-risk ICU patients
BACKGROUND Percutaneous dilatational tracheotomy (PDT) has become an established procedure in intensive care units (ICU). However, the safety of this method has been under debate given the growing number of critically ill patients with high bleeding risk receiving anticoagulation, dual antiplatelet therapy (DAPT) or even a combination of both, i.e. triple therapy. Therefore, the purpose of this study, including such a high proportion of patients on antithrombotic therapy, was to investigate whether PDT in high-risk ICU patients is associated with elevated procedural complications and to analyse the risk factors for bleeding occurring during and after PDT. METHODS PDT interventions conducted in ICUs at 12 European sites between January 2016 and October 2019 were retrospectively analysed for procedural complications. For subgroup analyses, patient stratification into clinically relevant risk groups based on anticoagulation and antiplatelet treatment regimens was performed and the predictors of bleeding occurrence were analysed. RESULTS In total, 671 patients receiving PDT were included and stratified into four clinically relevant antithrombotic treatment groups: (1) intravenous unfractionated heparin (iUFH, prophylactic dosage) (n = 101); (2) iUFH (therapeutic dosage) (n = 131); (3) antiplatelet therapy (aspirin and/or P2Y12 receptor inhibitor) with iUFH (prophylactic or therapeutic dosage) except for triple therapy (n = 290) and (4) triple therapy (DAPT with iUFH in therapeutic dosage) (n = 149). Within the whole cohort, 74 (11%) bleedings were reported to be procedure-related. Bleeding occurrence during and after PDT was independently associated with low platelet count (OR 0.73, 95% CI 0.56, 0.92, p = 0.009), chronic kidney disease (OR 1.75, 95{\%} CI 1.01, 3.03, p = 0.047) and previous stroke (OR 2.13, 95{\%} CI 1.1, 3.97, p = 0.02). CONCLUSION In this international, multicenter study bronchoscopy-guided PDT was a safe and low-complication airway management option, even in a cohort of high risk for bleeding on cardiovascular ICUs. Low platelet count, chronic kidney disease and previous stroke were identified as independent risk factors of bleeding during and after PDT but not triple therapy
Transformationen in der modellgetriebenen Software-Entwicklung
odellgetriebene Software-Entwicklung ist in den letzten Jahren
insbesondere unter Schlagworten wie MDA oder MDD zu einem Thema
von allgemeinem Interesse für die Software-Branche geworden.
Dabei ist ein Trend weg von der codezentrierten
Software-Entwicklung hin zum (Architektur-) Modell im
Mittelpunkt der Software-Entwicklung festzustellen.
Modellgetriebene Software-Entwicklung verspricht eine stetige
und automatisierte Synchronisation von Software-Modellen
verschiedenster Ebenen. Dies verspricht eine Verkürzung von
Entwicklungszyklen und mehr Produktivität. Primär wird nicht
mehr reiner Quellcode entwickelt, sondern Modelle und
Transformationen übernehmen als eine höhere Abstraktionsebene
die Rolle der Entwicklungssprache für Software-Entwickler.
Software-Architekturen lassen sich durch Modell beschreiben. Sie
sind weder auf eine Beschreibungssprache noch auf eine bestimmte
Domänen beschränkt. Im Zuge der Bemühungen modellgetriebener
Entwicklung lassen sich hier Entwicklungen hin zu
standardisierten Beschreibungssprachen wie UML aber auch
die Einführung von domänen-spezifischen Sprachen (DSL) erkennen.
Auf diese formalisierten Modelle lassen sich schließlich
Transformationen anwenden. Diese können entweder zu einem
weiteren Modell ("Model-to-Model") oder einer
textuellen Repräsentation ("Model-to-Text") erfolgen.
Transformationen kapseln dabei wiederholt anwendbares
Entwurfs-Wissen ("Muster") in parametrisierten Schablonen. Für
die Definition der Transformationen können Sprachen wie
beispielsweise QVT verwendet werden. Mit AndoMDA und
openArchitectureWare existieren Werkzeuge, welche die Entwickler
bei der Ausführung von Transformationen unterstützen
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