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Einzellige, mikroskopisch kleine, pflanzliche Organismen erweisen sich als ideale Bioindikatoren, um den Verunreinigungsgrad von Gewässern zu bestimmen: Diese Kieselalgen finden sich in den verschiedensten Gewässern - von reinsten Quellbächen bis zu Abwasserkanälen; die Artenzusammensetzung der Kieselalgen ist je nach Gewässerzustand sehr unterschiedlich. Auf jede Veränderung der Qualität folgt schnell ein charakteristischer Artenaustausch. Seit 1972 untersucht der Biologe Horst Lange-Bertalot mit dieser Methode die Wasserqualität des Mains, die sich wesentlich verbessert hat. Über Ergebnisse berichtet er gemeinsam mit Christine Schmidt.
Am 29. Oktober 2020 starb im hohen Alter von 93 Jahren im belgischen Genk der international renommierte Komparatist Hugo Dyserinck, langjähriger Leiter des nach seiner Emeritierung unrühmlich "abgewickelten" einstigen "Lehr- und Forschungsgebiets Komparatistik" in der Philosophischen Fakultät der RWTH Aachen. Der am 27. August 1927 im belgischen Brügge geborene Dyserinck wird vor allem als spiritus rector des "Aachener Programms" in Erinnerung bleiben. Er vermochte mit seiner imagologischen Version der Allgemeinen und Vergleichenden Literaturwissenschaft nicht nur Marksteine in der Komparatistik zu setzen, sondern wirkte darüber hinaus auch fruchtbar auf die kulturwissenschaftliche Europaforschung. Mit der von ihm jahrzehntelang in Theorie und Praxis entscheidend geprägten und propagierten komparatistischen Spezialdisziplin "Imagologie" lieferte der polyglotte Kosmopolit Dyserinck einen wichtigen Beitrag zur Dekonstruktion des Denkens in nationalen bzw. ethnischen Kategorien.
Methodik
(2002)
Die vegetationskundliche und strukturelle Zuordnung der Lebensraumtypen erfolgt nach der vorrangig von Braun-Blanquet entwickelten Vegetationsklassifizierung, einer hierarchischen Gliederung der Vegetationstypen (Syntaxonomie), die die Ebenen der Assoziation, des Verbandes, der Ordnung und der Klasse umfasst. Hierbei ist die Assoziation die grundlegende Einheit, in der die Pflanzengesellschaften zusammengefasst werden, die sich durch gleiche charakteristische Arten(gruppen)kombinationen auszeichnen. Der Verband vereinigt ähnliche Assoziationen. Das sind bereits umfassendere, jedoch standörtlich noch recht einheitliche Vegetationseinheiten. In Ordnungen werden ähnliche Verbände zusammengefasst. Die Klasse vereinigt ähnliche Ordnungen.
Der Nobelpreisträger Hans Albrecht Bethe war einer der ganz großen Physiker des 20. Jahrhunderts. Er gilt als einer der Väter der modernen Quantenphysik. In seiner Bedeutung für die Entwicklung der modernen Physik kommt er selbst Werner Heisenberg oder Max Planck sehr nahe. Er ist in Frankfurt aufgewachsen, hat hier das Goethe-Gymnasium besucht und an der Universität Frankfurt studiert. 1933 musste er emigrieren, da seine Mutter jüdischen Glaubens war. In seiner Heimatstadt Frankfurt ist er bisher fast unbekannt geblieben. Aus Sorge, dass Hitler-Deutschland »die Bombe« zuerst bauen könnte, unterstützte Bethe die USA bei der Entwicklung der Atombombe. Robert Oppenheimer holte ihn 1941 zum Manhattan Project nach Los Alamos (New Mexico). Hans Bethe war der führende theoretische Konstrukteur der Bombe. Doch Zeit seines Lebens glaubte er, damit das Falsche getan zu haben. Nach dem Krieg engagierte er sich für die Rüstungskontrolle. Bethe initiierte 1959 die Genfer Konferenz führender Forscher zur Empfehlung eines kontrollierten Teststoppabkommens und beriet den damaligen US-Präsidenten Dwight Eisenhower bei Fragen zur Einstellung von Kernwaffenversuchen. Er war in den USA und weltweit ein Wissenschaftler mit großem politischem und moralischem Einfluss. ...
Umzug des Fachbereichs Physik steht bevor : das Stern-Gerlach-Zentrum für experimentelle Physik
(2004)
Viscous hydrodynamic calculations of high energy heavy-ion collisions (Nb-Nb and Au-Au) from 200 to 800 MeV/nucleon are presented. The resulting baryon rapidity distributions, the in-plane transverse momentum transfer (bounce-off), and the azimuthal dependence of the midrapidity particles (off-plane squeeze out) compare well with Plastic Ball data. We find that the considered observables are sensitive both to the nuclear equation of state and to the nuclear shear viscosity η. Transverse momentum distributions indicate a high shear viscosity (η≊60 MeV/fm2 c) in the compression zone, in agreement with nuclear matter estimates. The bulk viscosity ζ influences only the entropy production during the expansion stage; collective observables like flow and dN/dY do not depend strongly on ζ. The recently observed off-plane (φ=90°) squeeze-out, which is found in the triple-differential rapidity distribution, exhibits the strongest sensitivity to the nuclear equation of state. It is demonstrated that for very central collisions, b=1 fm, the squeeze-out is visible even in the double-differential cross section. This is experimentally accessible by studying azimuthally symmetric events, as confirmed recently by data of the European 4π detector collaboration at Gesellchaft für Schwerionforschung Darmstadt.
Aims: Carotid intima media thickness (CIMT) predicts cardiovascular (CVD) events, but the predictive value of CIMT change is debated. We assessed the relation between CIMT change and events in individuals at high cardiovascular risk.
Methods and results: From 31 cohorts with two CIMT scans (total n = 89070) on average 3.6 years apart and clinical follow-up, subcohorts were drawn: (A) individuals with at least 3 cardiovascular risk factors without previous CVD events, (B) individuals with carotid plaques without previous CVD events, and (C) individuals with previous CVD events. Cox regression models were fit to estimate the hazard ratio (HR) of the combined endpoint (myocardial infarction, stroke or vascular death) per standard deviation (SD) of CIMT change, adjusted for CVD risk factors. These HRs were pooled across studies.
In groups A, B and C we observed 3483, 2845 and 1165 endpoint events, respectively. Average common CIMT was 0.79mm (SD 0.16mm), and annual common CIMT change was 0.01mm (SD 0.07mm), both in group A. The pooled HR per SD of annual common CIMT change (0.02 to 0.43mm) was 0.99 (95% confidence interval: 0.95–1.02) in group A, 0.98 (0.93–1.04) in group B, and 0.95 (0.89–1.04) in group C. The HR per SD of common CIMT (average of the first and the second CIMT scan, 0.09 to 0.75mm) was 1.15 (1.07–1.23) in group A, 1.13 (1.05–1.22) in group B, and 1.12 (1.05–1.20) in group C.
Conclusions: We confirm that common CIMT is associated with future CVD events in individuals at high risk. CIMT change does not relate to future event risk in high-risk individuals.
Aims: Averaged measurements, but not the progression based on multiple assessments of carotid intima-media thickness, (cIMT) are predictive of cardiovascular disease (CVD) events in individuals. Whether this is true for conventional risk factors is unclear.
Methods and results: An individual participant meta-analysis was used to associate the annualised progression of systolic blood pressure, total cholesterol, low-density lipoprotein cholesterol and high-density lipoprotein cholesterol with future cardiovascular disease risk in 13 prospective cohort studies of the PROG-IMT collaboration (n = 34,072). Follow-up data included information on a combined cardiovascular disease endpoint of myocardial infarction, stroke, or vascular death. In secondary analyses, annualised progression was replaced with average. Log hazard ratios per standard deviation difference were pooled across studies by a random effects meta-analysis. In primary analysis, the annualised progression of total cholesterol was marginally related to a higher cardiovascular disease risk (hazard ratio (HR) 1.04, 95% confidence interval (CI) 1.00 to 1.07). The annualised progression of systolic blood pressure, low-density lipoprotein cholesterol and high-density lipoprotein cholesterol was not associated with future cardiovascular disease risk. In secondary analysis, average systolic blood pressure (HR 1.20 95% CI 1.11 to 1.29) and low-density lipoprotein cholesterol (HR 1.09, 95% CI 1.02 to 1.16) were related to a greater, while high-density lipoprotein cholesterol (HR 0.92, 95% CI 0.88 to 0.97) was related to a lower risk of future cardiovascular disease events.
Conclusion: Averaged measurements of systolic blood pressure, low-density lipoprotein cholesterol and high-density lipoprotein cholesterol displayed significant linear relationships with the risk of future cardiovascular disease events. However, there was no clear association between the annualised progression of these conventional risk factors in individuals with the risk of future clinical endpoints.
Correction to: Infection (2020) 48:723–733 https://doi.org/10.1007/s15010-020-01469-6. The original version of this article unfortunately contained a mistake. In this article the authors Dirk Schürmann at affiliation Charité, University Medicine, Berlin, Olaf Degen at affiliation University Clinic Hamburg Eppendorf, Hamburg and Heinz-August Horst at affiliation University Hospital Schleswig–Holstein, Kiel, Germany were missing from the author list. The original article has been corrected.
The COLTRIMS Reaction Microscope C-REMI can image the momentum vectors of all emitted charged fragments in an atomic or molecular reactions similar to the bubble chamber in high energy particle physics. C-REMI can detect fragments with “zero” kinetic energy in an ultrahigh vacuum environment by projecting them with weak electromagnetic fields onto position-sensitive detectors. Geometrically a nearly 4π collection solid angle and a nearly 50% efficiency for a fivefold multi-coincidence can be achieved. Measuring time-of-flight and detector position the momenta of the fragments can be measured with excellent resolution (<0.01 a.u.; see A1 in the Appendix). Thus, multivector correlations in momentum space are measured, which provide insight into the entangled dynamics of atomic and molecular quantum systems. From these vector-correlations phases and energies can be deduced which allow for relative time measurements even in the zeptosecond range. C-REMI provides a “spyhole” into the secrets of ultrafast dynamics of atomic and molecular processes. It is applied today around the globe in numerous research projects in physics and chemistry. The purpose for writing this article is to demonstrate the universal application possibilities of C-REMI, and its high multi-coincidence efficiency and high momentum resolution. This paper will not give a review on all milestone experiments performed with C-REMI.
A small electrostatic storage ring is the central machine of the Frankfurt Ion Storage Experiments (FIRE) which will be built at the new Stern-Gerlach Center of Frankfurt University. As a true multiuser, multipurpose facility with ion energies up to 50 keV, it will allow new methods to analyze complex many-particle systems from atoms to very large biomolecules. With envisaged storage times of some seconds and beam emittances in the order of a few mm mrad, measurements with up to 6 orders of magnitude better resolutions as compared to single-pass experiments become possible. In comparison to earlier designs, the ring lattice was modified in many details: Problems in earlier designs were related to, e.g., the detection of light particles and highly charged ions with different charge states. Therefore, the deflectors were redesigned completely, allowing a more flexible positioning of the diagnostics. Here, after an introduction to the concept of electrostatic machines, an overview of the planned FIRE is given and the ring lattice and elements are described in detail.