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Correlations in azimuthal angle extending over a long range in pseudorapidity between particles, usually called the "ridge" phenomenon, were discovered in heavy-ion collisions, and later found in pp and p−Pb collisions. In large systems, they are thought to arise from the expansion (collective flow) of the produced particles. Extending these measurements over a wider range in pseudorapidity and final-state particle multiplicity is important to understand better the origin of these long-range correlations in small-collision systems. In this Letter, measurements of the long-range correlations in p−Pb collisions at sNN−−−√=5.02 TeV are extended to a pseudorapidity gap of Δη∼8 between particles using the ALICE, forward multiplicity detectors. After suppressing non-flow correlations, e.g., from jet and resonance decays, the ridge structure is observed to persist up to a very large gap of Δη∼8 for the first time in p−Pb collisions. This shows that the collective flow-like correlations extend over an extensive pseudorapidity range also in small-collision systems such as p−Pb collisions. The pseudorapidity dependence of the second-order anisotropic flow coefficient, v2({\eta}), is extracted from the long-range correlations. The v2(η) results are presented for a wide pseudorapidity range of −3.1<η<4.8 in various centrality classes in p−Pb collisions. To gain a comprehensive understanding of the source of anisotropic flow in small-collision systems, the v2(η) measurements are compared to hydrodynamic and transport model calculations. The comparison suggests that the final-state interactions play a dominant role in developing the anisotropic flow in small-collision systems.
The Chiral Magnetic Wave (CMW) phenomenon is essential to provide insights into the strong interaction in QCD, the properties of the quark-gluon plasma, and the topological characteristics of the early universe, offering a deeper understanding of fundamental physics in high-energy collisions. Measurements of the charge-dependent anisotropic flow coefficients are studied in Pb-Pb collisions at center-of-mass energy per nucleon-nucleon collision sNN−−−√= 5.02 TeV to probe the CMW. In particular, the slope of the normalized difference in elliptic (v2) and triangular (v3) flow coefficients of positively and negatively charged particles as a function of their event-wise normalized number difference, is reported for inclusive and identified particles. The slope rNorm3 is found to be larger than zero and to have a magnitude similar to rNorm2, thus pointing to a large background contribution for these measurements. Furthermore, rNorm2 can be described by a blast wave model calculation that incorporates local charge conservation. In addition, using the event shape engineering technique yields a fraction of CMW (fCMW) contribution to this measurement which is compatible with zero. This measurement provides the very first upper limit for fCMW, and in the 10-60% centrality interval it is found to be 26% (38%) at 95% (99.7%) confidence level.
Correlations in azimuthal angle extending over a long range in pseudorapidity between particles, usually called the "ridge" phenomenon, were discovered in heavy-ion collisions, and later found in pp and p−Pb collisions. In large systems, they are thought to arise from the expansion (collective flow) of the produced particles. Extending these measurements over a wider range in pseudorapidity and final-state particle multiplicity is important to understand better the origin of these long-range correlations in small-collision systems. In this Letter, measurements of the long-range correlations in p−Pb collisions at sNN−−−√=5.02 TeV are extended to a pseudorapidity gap of Δη∼8 between particles using the ALICE, forward multiplicity detectors. After suppressing non-flow correlations, e.g., from jet and resonance decays, the ridge structure is observed to persist up to a very large gap of Δη∼8 for the first time in p−Pb collisions. This shows that the collective flow-like correlations extend over an extensive pseudorapidity range also in small-collision systems such as p−Pb collisions. The pseudorapidity dependence of the second-order anisotropic flow coefficient, v2({\eta}), is extracted from the long-range correlations. The v2(η) results are presented for a wide pseudorapidity range of −3.1<η<4.8 in various centrality classes in p−Pb collisions. To gain a comprehensive understanding of the source of anisotropic flow in small-collision systems, the v2(η) measurements are compared to hydrodynamic and transport model calculations. The comparison suggests that the final-state interactions play a dominant role in developing the anisotropic flow in small-collision systems.
Measurements of charged-particle production in pp, p−Pb, and Pb−Pb collisions in the toward, away, and transverse regions with the ALICE detector are discussed. These regions are defined event-by-event relative to the azimuthal direction of the charged trigger particle, which is the reconstructed particle with the largest transverse momentum (ptrigT) in the range 8<ptrigT<15 GeV/c. The toward and away regions contain the primary and recoil jets, respectively; both regions are accompanied by the underlying event (UE). In contrast, the transverse region perpendicular to the direction of the trigger particle is dominated by the so-called UE dynamics, and includes also contributions from initial- and final-state radiation. The relative transverse activity classifier, RT=NTch/⟨NTch⟩, is used to group events according to their UE activity, where NTch is the charged-particle multiplicity per event in the transverse region and ⟨NTch⟩ is the mean value over the whole analysed sample. The energy dependence of the RT distributions in pp collisions at s√=2.76, 5.02, 7, and 13 TeV is reported, exploring the Koba-Nielsen-Olesen (KNO) scaling properties of the multiplicity distributions. The first measurements of charged-particle pT spectra as a function of RT in the three azimuthal regions in pp, p−Pb, and Pb−Pb collisions at sNN−−−√=5.02 TeV are also reported. Data are compared with predictions obtained from the event generators PYTHIA 8 and EPOS LHC. This set of measurements is expected to contribute to the understanding of the origin of collective-like effects in small collision systems (pp and p−Pb).
The Facility for Antiproton and Ion Research (FAIR), under construction at Darmstadt will provide intense relativistic beams of exotic nuclei at its Superconducting-FRagment Separator. High-resolution in-beam γ-ray spectroscopy will be performed in the HISPEC experiment, using the European Advanced GAmma-ray Tracking Array (AGATA). The PreSPEC-AGATA campaign is the predecessor of HISPEC and runs from 2012 to 2014 at GSI Helmholtzzentrum für Schwerionenforschung GmbH. Up to19 AGATA modules were used at GSI's F Ragment Separator in 2012. We report on the status of the experiment including preliminary results from performance commissioning.
Objectives: The SAVI-TF (Symetis ACURATE neo Valve Implantation Using Transfemoral Access) registry was initiated to study the ACURATE neo transcatheter heart valve in a large patient population treated under real-world conditions.
Background: The self-expanding, supra-annular ACURATE neo prosthesis is a transcatheter heart valve that gained the Conformité Européene mark in 2014, but only limited clinical data are available so far.
Methods: This prospective, multicenter registry enrolled 1,000 patients at 25 European centers who were followed for 1 year post-procedure.
Results: Mean patient age was 81.1 ± 5.2 years; mean logistic European System for Cardiac Operative Risk Evaluation I score, European System for Cardiac Operative Risk Evaluation II score, and Society of Thoracic Surgeons score were 18.1 ± 12.5%, 6.6 ± 7.5%, and 6.0 ± 5.6%, respectively. At 1 year, 8.0% (95% confidence interval [CI]: 6.3% to 9.7%) of patients had died, 2.3% (95% CI: 1.3% to 3.2%) had disabling strokes, and 9.9% (95% CI: 8.1% to 11.8%) had permanent pacemaker implantations. Through 1 year, 5 reinterventions (0.5%; 95% CI: 0.1% to 1.0%) were performed: 3 valve-in-valve and 2 surgical aortic valve replacements. Mean effective orifice area was 1.84 ± 0.43 cm2, mean gradient was 7.3 ± 3.7 mm Hg, and greater than mild paravalvular leakage was observed in 3.6% of patients.
Conclusions: Transfemoral implantation of the ACURATE neo prosthesis resulted in favorable 1-year clinical and echocardiographic outcomes with very low mortality and new pacemaker rates.
The editorial board of Aging reviews research papers published in 2009,which they believe have or will have a significant impact on aging research.Among many others, the topics include genes that accelerate aging or incontrast promote longevity in model organisms, DNA damage responsesand telomeres, molecular mechanisms of life span extension by calorierestriction and pharmacologic interventions into aging. The emergingmessage in 2009 is that aging is not random but determined by agenetically-regulated longevity network and can be decelerated bothgenetically and pharmacologically.
Einfache elektrochemische Methode zur Bestimmung von Chlorit in wässrigen und nicht-wässrigen Systemen Stoffe bzw. Verbindungen, welche nachweislich krebserregend oder fruchtbarkeitsschädigend sind, werden seit Jahren, insbesondere durch die WHO, streng reguliert. Zu diesen Stoffen zählt u. a. Chlorit, welches als Abbauprodukt in Desinfektionsmitteln, Poolwassern und im Rahmen von organischen Oxidationsprozessen vorkommt. Im Rahmen des Projektes sollte eine elektrochemische Methode zu Detektion von Chlorit in wässrigen und organischen Proben entwickelt werden, wobei auf eine Glaskohlenstoffelektrode in Kombination mit Li [NTf]2 im Wässrigen und [Bmpyrr][NTf]2/MeOH im Organischen als Elektrolyten zurückgegriffen wurden.
Bei der Methodenentwicklung wurde auf Differentielle-Puls-Voltammetrie zurückgegriffen, da diese im Vergleich zum Cyclovoltammetrie deutlich empfindlicher ist. Die Methodenvalidierung nach ICH-Guidelines konnte erfolgreich durchgeführt werden Dabei konnte im Wässrigen eine Nachweisgrenze von 0.07 mg L-1 (Organisch: 0.20 mg L-1) erhalten werden. Beide lagen deutlich unter den WHO-Grenzwerten von 0.7 mg L-1. Die Selektivität/Interferenz wurde gegenüber den übrigen Chlor-Spezies getestet; für alle Spezies, außer Hypochlorit, konnten für die Wiederfindungsrate von Chlorit Werte nahe 100% erhalten werden. Die entwickelte Methode konnte erfolgreich auf wässrige (Poolproben, Desinfektionsmittel) und organische Proben (aus Pinnick-Synthesen) angewendet werden. Insbesondere durch die Anwendung im Bereich der Pinnick-Oxidation war der Sensor für mögliche In-Line-Analytik geeignet. Bei den organischen Proben konnte zudem die ionische Flüssigkeit zu 92% zurückgewonnen werden, was den Elektrolyten in Hinblick auf Nachhaltigkeit und Wirtschaftlichkeit noch attraktiver macht.
Entwicklung ionenchromatographischer Methoden zur Detektion von Chloroxo-Spezies
Der Bedarf an schnellen, kostengünstigen Analysemethoden, welche den Vorgaben der einzelnen Behörden weltweit entsprechen, ist in den letzten Jahren enorm gestiegen. Im Rahmen des Projektes sollte eine ionenchromatographische Methode (IC) entwickelt werden, welche neben den Chloroxo-Spezies (Chlorid, Hypochlorit, Chlorit, Chlorat und Perchlorat) auch die bekannten Standardionen (Fluorid, Bromid, Nitrat, Phosphat, Sulfat, Iodid) nachweisbar macht. Zunächst gelang es, die Methodenparameter zu optimieren und so die Chloro-Spezies, außer Hypochlorit, von den übrigen Standardanionen innerhalb von 50 Minuten vollständig zu trennen. Die Methode konnte in der weiteren Entwicklung sogar noch um die Detergenzien-Anionen Acetat, Formiat, Oxalat und Tartrat erweitert werden. (ASupp 7, 45 °C, 0.8 mL min-1, 6 mmol L-1 Na2CO3 / 1 mmol L-1 NaHCO3 + 10% Acetonitril). Auch alle notwendigen Validierungsparameter konnten erfolgreich bestimmt werden. Zuletzt war es möglich, erfolgreich unterschiedliche Realproben zu vermessen.
Da ein Nachweis von Hypochlorit mittels IC nicht möglich war, wurden weitere Anstrengung unternommen, dieses Anion mittels IC-PCR (Nachsäulenderivatisierung) nachzuweisen. Als Detektionsprinzip wurde dabei auf eine Bromat-Nachweis-Methode mittels UV/VIS zurückgegriffen, welche im Rahmen des Projektes angepasst wurde. Da davon ausgegangen werden muss, dass das Hypochlorit mit reaktiven Stellen innerhalb des Säulenmaterials reagiert und somit nicht mehr detektiert werden kann, wurden Passivierungsexperimente an der Vorsäule und Säule für 24 h mit einer Hypochlorit-NaOH-Mischung durchgeführt. Nach 60 Stunden Passivierung konnten erstmals reproduzierbare Ergebnisse bei dem Nachweis von OCl- erhalten werden. Zuletzt konnten erfolgreich fünf unterschiedliche Realproben vermessen und der Hypochlorit-Gehalt mit bisher angewandten Methoden verglichen werden, wobei die erhaltenen Werte in der gleichen Größenordnung lagen.
Entwicklung eines Sensors unter Verwendung der Viologen-Grundstruktur auf metallischen Oberflächen
Früher fanden Viologene und deren Derivate Anwendung im Bereich der Schädlingsbekämpfung und wurden hauptsächlich als Kontaktherbizid verwendet. Mittlerweile hat sich das Anwendungsspektrum der Viologene deutlich verändert, u.a. werden die in organischen Redox-Fluss-Batterien als Elektrolyte eingesetzt. Im Rahmen diesen Projekts wurden mehrere bekannte Viologen-Grundkörper (u. A. Methylviologen (MV)) vollständig elektrochemisch charakterisiert Im Anschluss wurde MV mit unterschiedlichen Ankergruppen (Thiol-, Sulfonat, -Phosphonat-, Carboxylanker) modifiziert und auf metallische Oberfläche (u. A. Gold und Kupfer) abgeschieden mit dem Ziel ein neues Sensor-Motiv für die Analytik zu entwickeln. Der Thiolanker konnte erfolgreich auf Gold, der Carboxylanker erfolgreich auf Kupfer abgeschieden werden. Die anschließenden elektrochemischen Untersuchungen der abgeschiedenen Monolagen ergaben jedoch eine geringe Stabilität der Anker in wässriger und organischer Umgebung, sodass in Zukunft weitere Anstrengungen unternommen werden müssen, die Stabilität des Viologensystems auf der Oberfläche zu verbessern.
Background The COVID-19 pandemic has spurred large-scale, inter-institutional research efforts. To enable these efforts, researchers must agree on dataset definitions that not only cover all elements relevant to the respective medical specialty but that are also syntactically and semantically interoperable. Following such an effort, the German Corona Consensus (GECCO) dataset has been developed previously as a harmonized, interoperable collection of the most relevant data elements for COVID-19-related patient research. As GECCO has been developed as a compact core dataset across all medical fields, the focused research within particular medical domains demands the definition of extension modules that include those data elements that are most relevant to the research performed in these individual medical specialties.
Objective To (i) specify a workflow for the development of interoperable dataset definitions that involves a close collaboration between medical experts and information scientists and to (ii) apply the workflow to develop dataset definitions that include data elements most relevant to COVID-19-related patient research in immunization, pediatrics, and cardiology.
Methods We developed a workflow to create dataset definitions that are (i) content-wise as relevant as possible to a specific field of study and (ii) universally usable across computer systems, institutions, and countries, i.e., interoperable. We then gathered medical experts from three specialties (immunization, pediatrics, and cardiology) to the select data elements most relevant to COVID-19-related patient research in the respective specialty. We mapped the data elements to international standardized vocabularies and created data exchange specifications using HL7 FHIR. All steps were performed in close interdisciplinary collaboration between medical domain experts and medical information scientists. The profiles and vocabulary mappings were syntactically and semantically validated in a two-stage process.
Results We created GECCO extension modules for the immunization, pediatrics, and cardiology domains with respect to the pandemic requests. The data elements included in each of these modules were selected according to the here developed consensus-based workflow by medical experts from the respective specialty to ensure that the contents are aligned with the respective research needs. We defined dataset specifications for a total number of 48 (immunization), 150 (pediatrics), and 52 (cardiology) data elements that complement the GECCO core dataset. We created and published implementation guides and example implementations as well as dataset annotations for each extension module.
Conclusions These here presented GECCO extension modules, which contain data elements most relevant to COVID-19-related patient research in immunization, pediatrics and cardiology, were defined in an interdisciplinary, iterative, consensus-based workflow that may serve as a blueprint for the development of further dataset definitions. The GECCO extension modules provide a standardized and harmonized definition of specialty-related datasets that can help to enable inter-institutional and cross-country COVID-19 research in these specialties.
Background: The COVID-19 pandemic has spurred large-scale, inter-institutional research efforts. To enable these efforts, the German Corona Consensus (GECCO) dataset has been developed previously as a harmonized, interoperable collection of the most relevant data elements for COVID-19-related patient research. As GECCO has been developed as a compact core dataset across all medical fields, the focused research within particular medical domains demanded the definition of extension modules that include those data elements that are most relevant to the research performed in these individual medical specialties.
Main body: We created GECCO extension modules for the immunization, pediatrics, and cardiology domains with respect to the pandemic requests. The data elements included in each of these modules were selected in a consensus-based process by working groups of medical experts from the respective specialty to ensure that the contents are aligned with the research needs of the specialty. The selected data elements were mapped to international standardized vocabularies and data exchange specifications were created using HL7 FHIR profiles on the appropriate resources. All steps were performed in close interdisciplinary collaboration between medical domain experts, medical information scientists and FHIR developers. The profiles and vocabulary mappings were syntactically and semantically validated in a two-stage process. In that way, we defined dataset specifications for a total number of 23 (immunization), 59 (pediatrics), and 50 (cardiology) data elements that augment the GECCO core dataset. We created and published implementation guides and example implementations as well as dataset annotations for each extension module.
Conclusions: We here present extension modules for the GECCO core dataset that contain data elements most relevant to COVID-19-related patient research in immunization, pediatrics and cardiology. These extension modules were defined in an interdisciplinary, iterative, consensus-based approach that may serve as a blueprint for the development of further dataset definitions and GECCO extension modules. The here developed GECCO extension modules provide a standardized and harmonized definition of specialty-related datasets that can help to enable inter-institutional and cross-country COVID-19 research in these specialties.